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Sample records for fischer-tropsch catalysts quarterly

  1. Catalysts for Fischer-Tropsch

    SciTech Connect

    Srivastava, R.D. ); Rao, V.U.S.; Cinquegrane, G.; Stiegel, G.J. )

    1990-02-01

    The slurry-phase Fischer-Tropsch (F-T) process has attracted considerable attention recently. The process can make liquid fuels by reacting hydrogen-lean synthesis gas produced from modern energy-efficient gasifiers. continuing assessment of Fischer-Tropsch Synthesis (FTS) has a high priority within an indirect liquefaction program, a part of the liquid fuels program sponsored by the U.S. Department of Energy (DOE) and executed by the Pittsburgh Energy Technology Center (PETC). Funding for the indirect liquefaction program in 1990:0090 is anticipated to be about $8.5 million compared to $6.6 million in 1989 and a like amount in the year before. The studies within the program are conducted by industry, universities, national laboratories and in-house PETC research and development. This article reviews preparation and properties of iron-based catalysts, including recent patent activities and in-depth process analysis of slurry-phase FTS. The review provides an analysis of Fischer-Tropsch catalyst research and development trends and describes options to increase selectivity for iron-based catalysts in a slurry phase.

  2. Development of precipitated iron Fischer-Tropsch catalysts. Quarterly technical progress report, April 1, 1995--June 30, 1995

    SciTech Connect

    Bukur, D.B.; Lang, X.; Wei, G.; Xiao, S.

    1995-08-17

    Work continued on the development of catalysts for Fischer-Tropsch synthesis. Six catalysts were synthesised. The effects of a calcium oxide promoter were evaluated. Catalysts were characterized for pore size and BET surface area.

  3. Fischer-Tropsch Catalysts

    NASA Technical Reports Server (NTRS)

    White, James H. (Inventor); Taylor, Jesse W. (Inventor)

    2008-01-01

    Catalyst compositions and methods for F-T synthesis which exhibit high CO conversion with minor levels (preferably less than 35% and more preferably less than 5%) or no measurable carbon dioxide generation. F-T active catalysts are prepared by reduction of certain oxygen deficient mixed metal oxides.

  4. Novel Fischer-Tropsch catalysts. [DOE patent

    DOEpatents

    Vollhardt, K.P.C.; Perkins, P.

    Novel compounds are described which are used as improved Fischer-Tropsch catalysts particularly for the conversion of CO + H/sub 2/ to gaseous and liquid hydrocarbons at milder conditions than with prior catalysts.

  5. Technology development for iron Fischer-Tropsch catalysts. Quarterly report, April--June 1993

    SciTech Connect

    Davis, B.H.

    1993-11-01

    The Fischer-Tropsch process has attracted a great deal of attention in terms of catalytic activity and selectivity to produce higher number hydrocarbons by reacting carbon monoxide and hydrogen at high pressures in the presence of catalysts. Shortly after the initial discovery, Fischer and Tropsch developed more active catalysts for indirect liquefaction. The product distribution resulting from the Fischer-Tropsch synthesis (FTS) varies widely depending upon the catalysts, the temperature and pressure of reactions, pretreatment conditions, etc. It is desirable to improve the selectivity while maintaining the activity intact. One approach to achieve this task is the addition of promoters such as oxides of K, Mn, Ti, Mo, Ni, and Co, etc. It was observed that most of these promoted catalysts exhibit an increase in selectivity to higher hydrocarbons. For example, the addition of thoria as a promoter to cobalt-kieselguhr catalysts resulted in an enhanced yield of C{sub 5}{sup +} hydrocarbons. Even a small amount of thoria promoter ({approximately}0.4 wt %) addition to Co/ZSM-5 causes a remarkable increase in the conversion, shift activity, and C{sub 5}{sup +} selectivity. Thoria added as a promoter to a precipitated iron oxide catalyst appears to decrease wax selectivity. It is generally believed that the factors such as dispersion effects of rare earth oxides and thoria, the redox properties, and the basic properties of rare earth oxides and thorium oxides, greatly influence the activity and selectivity.

  6. Moderated ruthenium fischer-tropsch synthesis catalyst

    DOEpatents

    Abrevaya, Hayim

    1991-01-01

    The subject Fischer-Tropsch catalyst comprises moderated ruthenium on an inorganic oxide support. The preferred moderator is silicon. Preferably the moderator is effectively positioned in relationship to ruthenium particles through simultaneous placement on the support using reverse micelle impregnation.

  7. Novel Fischer-Tropsch catalysts

    DOEpatents

    Vollhardt, Kurt P. C.; Perkins, Patrick

    1981-01-01

    Novel polymer-supported metal complexes of the formula: PS --R Me(CO).sub.n H.sub.m where: PS represents a divinylbenzene crosslinked polystyrene in which the divinylbenzene crosslinking is greater than 1% and less than about 18%; R represents a cycloalkadienyl radical of 4 through 6 carbon atoms; Me represents a Group VIII metal; CO represents a carbonyl radical; H represents hydrogen; n represents an integer varying from 0 through 3; m represents an integer varying from 0 through 2 inclusively with the further provision that 2n+m must total 18 when added to the electrons in R and Me, or n+m must total 0; are prepared by: brominating PS --H by treating same with bromine in the presence of a thallium salt in a partially or fully halogenated solvent to form PS --Br; treating said PS --Br so produced with a lithium alkyl of 1 through 12 carbon atoms in an aromatic solvent to produce PS --Li; substituting said PS-- Li so produced by reaction with a 2-cycloalkenone of 4 to 6 carbon atoms in the presence of an ether solvent and using a water work-up to form a cycloalkenylalcohol-substituted PS ; dehydrating said alcohol so produced by heating under a vacuum to produce a cycloalkadienyl-substituted PS ; reacting the cycloalkadienyl-substituted PS with metal carbonyl in the presence of a partially or fully halogenated hydrocarbon, aromatic hydrocarbon of 6 through 8 carbon atoms, ethers, or esters of 4 through 10 carbon atoms as a solvent to produce a polystyrene-supported cycloalkadienyl metal carbonyl. The novel compounds are used as improved Fischer-Tropsch catalysts particularly for the conversion of CO+H.sub.2 to gaseous and liquid hydrocarbons at milder conditions than with prior catalysts.

  8. Novel Fischer-Tropsch catalysts

    DOEpatents

    Vollhardt, Kurt P. C.; Perkins, Patrick

    1981-01-01

    Novel polymer-supported metal complexes of the formula PS -R Me(CO).sub.n H.sub.m where: PS represents a divinylbenzene crosslinked polystyrene in which the divinylbenzene crosslinking is greater than 1% and less than about 18%; R represents a cycloalkadienyl radical of 4 through 6 carbon atoms; Me represents a Group VIII metal; CO represents a carbonyl radical; H represents hydrogen; n represents an integer varying from 0 through 3; m represents an integer varying from 0 through 2 inclusively with the further provision that 2n+m must total 18 when added to the electrons in R and Me, or n+m must total 0; are prepared by: brominating PS -H by treating same with bromine in the presence of a thallium salt in a partially or fully halogenated solvent to form PS -Br; treating said PS -Br so produced with a lithium alkyl of 1 through 12 carbon atoms in an aromatic solvent to produce PS -Li; substituting said PS - Li so produced by reaction with a 2-cycloalkenone of 4 to 6 carbon atoms in the presence of an ether solvent and using a water work-up to form a cycloalkenylalcohol-substituted PS ; dehydrating said alcohol so produced by heating under a vacuum to produce a cycloalkadienyl-substituted PS ; reacting the cycloalkadienyl-substituted PS with metal carbonyl in the presence of a partially or fully halogenated hydrocarbon, aromatic hydrocarbon of 6 through 8 carbon atoms, ethers, or esters of 4 through 10 carbon atoms as a solvent to produce a polystyrene-supported cycloalkadienyl metal carbonyl. The novel compounds are used as improved Fischer-Tropsch catalysts particularly for the conversion of CO+H.sub.2 to gaseous and liquid hydrocarbons at milder conditions than with prior catalysts.

  9. Novel Fischer-Tropsch catalysts

    DOEpatents

    Vollhardt, Kurt P. C.; Perkins, Patrick

    1980-01-01

    Novel polymer-supported metal complexes of the formula: PS --R Me(CO).sub.n H.sub.m where: PS represents a divinylbenzene crosslinked polystyrene in which the divinylbenzene crosslinking is greater than 1% and less than about 18%; R represents a cycloalkadienyl radical of 4 through 6 carbon atoms; Me represents a Group VIII metal; CO represents a carbonyl radical; H represents hydrogen; n represents an integer varying from 0 through 3; m represents an integer varying from 0 through 2 inclusively with the further provision that 2n+m must total 18 when added to the electrons in R and Me, or n+m must total 0; are prepared by: brominating PS --H by treating same with bromine in the presence of a thallium salt in a partially or fully halogenated solvent to form PS --Br; treating said PS --Br so produced with a lithium alkyl of 1 through 12 carbon atoms in an aromatic solvent to produce PS --Li; substituting said PS-- Li so produced by reaction with a 2-cycloalkenone of 4 to 6 carbon atoms in the presence of an ether solvent and using a water work-up to form a cycloalkenylalcohol-substituted PS ; dehydrating said alcohol so produced by heating under a vacuum to produce a cycloalkadienyl-substituted PS ; reacting the cycloalkadienyl-substituted PS with metal carbonyl in the presence of a partially or fully halogenated hydrocarbon, aromatic hydrocarbon of 6 through 8 carbon atoms, ethers, or esters of 4 through 10 carbon atoms as a solvent to produce a polystyrene-supported cycloalkadienyl metal carbonyl. The novel compounds are used as improved Fischer-Tropsch catalysts particularly for the conversion of CO+H.sub.2 to gaseous and liquid hydrocarbons at milder conditions than with prior catalysts.

  10. Novel Attrition-Resistant Fischer Tropsch Catalyst

    SciTech Connect

    Weast, Logan, E.; Staats, William, R.

    2009-05-01

    There is a strong national interest in the Fischer-Tropsch synthesis process because it offers the possibility of making liquid hydrocarbon fuels from reformed natural gas or coal and biomass gasification products. This project explored a new approach that had been developed to produce active, attrition-resistant Fischer-Tropsch catalysts that are based on glass-ceramic materials and technology. This novel approach represented a promising solution to the problem of reducing or eliminating catalyst attrition and maximizing catalytic activity, thus reducing costs. The technical objective of the Phase I work was to demonstrate that glass-ceramic based catalytic materials for Fischer-Tropsch synthesis have resistance to catalytic deactivation and reduction of particle size superior to traditional supported Fischer-Tropsch catalyst materials. Additionally, these novel glass-ceramic-based materials were expected to exhibit catalytic activity similar to the traditional materials. If successfully developed, the attrition-resistant Fischer-Tropsch catalyst materials would be expected to result in significant technical, economic, and social benefits for both producers and public consumers of Fischer-Tropsch products such as liquid fuels from coal or biomass gasification. This program demonstrated the anticipated high attrition resistance of the glass-ceramic materials. However, the observed catalytic activity of the materials was not sufficient to justify further development at this time. Additional testing documented that a lack of pore volume in the glass-ceramic materials limited the amount of surface area available for catalysis and consequently limited catalytic activity. However, previous work on glass-ceramic catalysts to promote other reactions demonstrated that commercial levels of activity can be achieved, at least for those reactions. Therefore, we recommend that glass-ceramic materials be considered again as potential Fischer-Tropsch catalysts if it can be

  11. Catalyst and reactor development for a liquid-phase Fischer-Tropsch process. Quarterly technical progress report, 1 April 1981-30 June 1981

    SciTech Connect

    Brockington, J.W.; Dyer, P.N.; Pierantozzi, R.; Brain, B.W.; Bauer, J.V.

    1981-07-01

    In October 1980, Air Products and Chemicals, Inc. began a three year contract with the DOE: Catalyst and Reactor Development for a Liquid Phase Fischer-Tropsch Process. The program contains four major tasks: (1) Project Work Plan, (2) Slurry Catalyst Development, (3) Slurry Reactor Design Studies, and (4) Pilot Facility Design. This report describes work on Tasks 2 and 3 carried out in the third quarter of the contract. In Task 2, the computerized search of the Fischer-Tropsch literature was continued, and improvements were made in data processing programs. Shakedown tests were completed on the first 300 ml slurry reactor, and construction of the second and third reactors began. Five modified conventional slurry catalysts were prepared, and two batches were tested in the gas phase giving information on selectivity as a function of composition and activation. Four supported cluster catalyst were synthesized, and seven were tested in the gas phase.

  12. Development of process evaluation of improved Fischer-Tropsch slurry catalysts. Quarterly technical progress report, 1 April--30 June 1988

    SciTech Connect

    Withers, H.P.; Bukur, D.B.; Rosynek, M.P.

    1988-12-31

    The objective of this contract is to develop a consistent technical data base on the use of iron-based catalysts in Fischer-Tropsch (FT) synthesis reactions. This data base will be developed to allow the unambiguous comparison of the performance of these catalysts with each other and with state-of-the-art iron catalyst compositions. Particular attention will be devoted to generating reproducible kinetic and selectivity data and to developing reproducible improved catalyst compositions.

  13. Development and process evaluation of improved Fischer-Tropsch slurry catalysts. Quarterly technical progress report, 1 October-31 December 1987

    SciTech Connect

    Withers, H.P.; Bukur, D.B.; Rosynek, M.P.

    1987-12-31

    The objective of this contract is to develop a consistent technical data base on the use of iron-based catalysts in Fischer-Tropsch (FT) synthesis reactions. This data base will be developed to allow the unambiguous comparison of the performance of these catalysts with each other and with state-of-the-art iron catalyst compositions. Particular attention will be devoted to generating reproducible kinetic and selectivity data and to developing reproducible improved catalyst compositions.

  14. Development and process evaluation of improved Fischer-Tropsch slurry catalysts. Quarterly technical progress report, 1 July--30 September 1988

    SciTech Connect

    Withers, H.P.; Bukur, D.B.; Rosynek, M.P.

    1988-12-31

    The objective of this contract is to develop a consistent technical data base on the use of iron-based catalysts in Fischer-Tropsch (F-T) synthesis reactions. This data base will be developed to allow the unambiguous comparison of the performance of these catalysts with each other and with state-of-the-art iron catalyst compositions. Particular attention will be devoted to generating reproducible kinetic and selectivity data and to developing reproducible improved catalyst compositions.

  15. Development and process evaluation of improved Fischer-Tropsch slurry catalysts. Quarterly technical progress report, 1 October--31 December 1988

    SciTech Connect

    Withers, H.P.; Bukur, D.B.; Rosynek, M.P.

    1988-12-31

    The objective of this contract is to develop a consistent technical data base on the use of iron-based catalysts in Fischer-Tropsch (FT) synthesis reactions. This data base will be developed to allow the unambiguous comparison of the performance of these catalysts with each other and with state-of-the-art iron catalyst compositions. Particular attention will be devoted to generating reproducible kinetic and selectivity data and to developing reproducible improved catalyst compositions.

  16. Catalyst structure and method of Fischer-Tropsch synthesis

    DOEpatents

    Wang, Yong; Vanderwiel, David P.; Tonkovich, Anna Lee Y.; Gao, Yufei; Baker, Eddie G.

    2004-06-15

    The present invention includes Fischer-Tropsch catalysts, reactions using Fischer-Tropsch catalysts, methods of making Fischer-Tropsch catalysts, processes of hydrogenating carbon monoxide, and fuels made using these processes. The invention provides the ability to hydrogenate carbon monoxide with low contact times, good conversion rates and low methane selectivities. In a preferred method, the catalyst is made using a metal foam support.

  17. Catalyst structure and method of fischer-tropsch synthesis

    DOEpatents

    Wang, Yong [Richland, WA; Vanderwiel, David P [Richland, WA; Tonkovich, Anna Lee Y [Pasco, WA; Gao, Yufei [Kennewick, WA; Baker, Eddie G [Pasco, WA

    2002-12-10

    The present invention includes Fischer-Tropsch catalysts, reactions using Fischer-Tropsch catalysts, methods of making Fischer-Tropsch catalysts, processes of hydrogenating carbon monoxide, and fuels made using these processes. The invention provides the ability to hydrogenate carbon monoxide with low contact times, good conversion rates and low methane selectivities. In a preferred method, the catalyst is made using a metal foam support.

  18. Diffusion limitations in Fischer-Tropsch catalysts

    SciTech Connect

    Post, M.F.M.; Van'tHoog, A.C.; Minderhoud, J.K.; Sie, S.T. . Lab.)

    1989-07-01

    The extent of diffusion limitations in the catalytic conversion of synthesis gas to hydrocarbons by the Fischer-Tropsch reaction has been established for a number of iron- and cobalt-based catalysts. The studies were performed in a fixed-bed microreactor system at temperatures in the range 473-523 {Kappa}. Variation of catalyst particle size in the range 0.2.-2.6 mm shows that the conversion of synthesis gas decreases considerably when the average particle size is increased. The effects of variation of particle size and pore diameter have been quantified with the Thiele model for diffusion limitations. Evidence has accumulated that the limited mobility of reactant molecules in the liquid-filled pores of Fischer-Tropsch catalysts is the main cause of retardation of the reaction rates. The experimentally determined reaction rates with various catalysts operated under different conditions show an excellent fit with the theoretical model.

  19. Cobalt Fischer-Tropsch catalysts having improved selectivity

    DOEpatents

    Miller, James G.; Rabo, Jule A.

    1989-01-01

    A cobalt Fischer-Tropsch catalyst having an improved steam treated, acid extracted LZ-210 support is taught. The new catalyst system demonstrates improved product selectivity at Fischer-Tropsch reaction conditions evidenced by lower methane production, higher C.sub.5.sup.+ yield and increased olefin production.

  20. Diffusion limitations in Fischer-Tropsch catalysts

    SciTech Connect

    Post, M.F.M.; Sie, S.T. Badhuisweg 3, 1031 CM Amsterdam )

    1988-01-01

    Indirect conversion of natural hydrocarbon resources such as natural gas into transportation fuels or chemicals usually involves the conversion to carbon monoxide and hydrogen (synthesis gas), followed by a catalytic conversion to the desired products via e.g. the Fischer-Tropsch (FT) reaction. In a fixed-bed mode of operation, the FT catalyst generally consists of particles of a few mm in size, for pressure-drop and heat-transfer considerations. To investigate whether diffusion limitations inside larger catalyst particles play a role during the synthesis reaction, the authors have made an extensive study using a number of iron- and cobalt-based catalysts, in which they have evaluated and quantified the effects of catalyst particle size and pore diameter on reaction rates. The effects due to variation of particle size and pore diameter have been quantified with the Thiele model for diffusion limitations.

  1. Reoxidation and deactivation of supported cobalt Fischer-Tropsch catalysts

    SciTech Connect

    Schanke, D.; Hilmen, A.M.; Bergene, E.

    1995-12-01

    The Fischer-Tropsch synthesis is an attractive possibility for conversion of natural gas into high quality liquid fuels. Due to its low water-gas shift activity, good activity/selectivity properties and relatively low price, cobalt is the choice of catalytic metal for natural gas conversion via Fischer-Tropsch synthesis. In the cobalt-catalyzed Fischer-Tropsch reaction, oxygen is mainly rejected as water. In this paper we describe the influence of water on supported cobalt catalysts. The deactivation of supported Co catalysts was studied in a fixed-bed reactor using synthesis gas feeds containing varying concentrations of water vapour.

  2. The optimally performing Fischer-Tropsch catalyst.

    PubMed

    Filot, Ivo A W; van Santen, Rutger A; Hensen, Emiel J M

    2014-11-17

    Microkinetics simulations are presented based on DFT-determined elementary reaction steps of the Fischer-Tropsch (FT) reaction. The formation of long-chain hydrocarbons occurs on stepped Ru surfaces with CH as the inserting monomer, whereas planar Ru only produces methane because of slow CO activation. By varying the metal-carbon and metal-oxygen interaction energy, three reactivity regimes are identified with rates being controlled by CO dissociation, chain-growth termination, or water removal. Predicted surface coverages are dominated by CO, C, or O, respectively. Optimum FT performance occurs at the interphase of the regimes of limited CO dissociation and chain-growth termination. Current FT catalysts are suboptimal, as they are limited by CO activation and/or O removal. PMID:25168456

  3. Reoxidation and deactivation of supported cobalt Fischer-Tropsch catalysts

    SciTech Connect

    Schanke, D.; Bergene, E.; Adnanes, E.

    1995-12-31

    As a result of the highly exothermic nature of the Fischer-Tropsch reaction, heat transfer considerations limit the maximum conversion per pass in fixed-bed processes, whereas slurry reactors can operate at higher conversions. During Fischer-Tropsch synthesis on cobalt catalysts, high conversions will generate high partial pressures of water at the reactor exit, due to the low water gas shift activity of cobalt. In addition, the extensive back-mixing in slurry reactors will give a relatively uniform concentration profile in the reactor, characterized by a high concentration of water and low reactant concentrations. From the commercial iron-catalyzed Fischer-Tropsch synthesis in fixed-bed (Arge) reactors it is known that the catalyst deactivates by oxidation of iron by CO{sub 2} and H{sub 2}O near the exit of the reactor. Although bulk oxidation of cobalt during Fischer-Tropsch synthesis is not thermodynamically favored, it was early speculated that surface oxidation of cobalt could occur during Fischer-Tropsch synthesis. The purpose of the present work is to describe the influence of water on the deactivation behavior of Al{sub 2}O{sub 3} supported cobalt catalysts. The possibility of cobalt oxidation during Fischer-Tropsch synthesis was investigated by model studies.

  4. Separation of Fischer-Tropsch wax from catalyst by supercritical extraction. Quarterly report, July 1, 1996 - September 30, 1996

    SciTech Connect

    Joyce, P.C.; Thies, M.C.; Sherrard, D.; Biales, J.; Kilpatrick, P.; Roberts, G.

    1996-12-31

    The objective of this research projects is to evaluate the potential of SCF extraction for separating the catalyst slurry of a Fischer- Tropsch (F-T) slurry bubble column (SBC) reactor into two fractions: (1) a catalyst-free wax containing less than 10 ppm particulate matter and (2) a concentrated catalyst slurry that is ready for recycle or regeneration. The wax will be extracted with a hydrocarbon solvent that has a critical temperature near the operating temperature of the SBC reactor, i.e. 200-300{degrees}C. Initial work is being performed using n-hexane as the solvent. The success of the projects depends on two major factors. First, the supercritical solvent must be able to dissolve the F-T wax; furthermore, the must be accomplished without entraining the solid catalyst. Second, the extraction must be controlled so as not to favor the removal of the low molecular weight wax compounds, i.e., a constant carbon-number distribution of the alkanes in the wax slurry must be maintained at steady-state column operation. The project includes three tasks (1) equilibrium solubility measurements, (2) thermodynamic modeling, and (3) process design studies.

  5. Cobalt Fischer-Tropsch catalysts having improved selectivity

    DOEpatents

    Miller, James G.; Rabo, Jule A.

    1989-01-01

    The promoter(s) Mn oxide or Mn oxide and Zr oxide are added to a cobalt Fischer-Tropsch catalyst combined with the molecular sieve TC-103 or TC-123 such that the resultant catalyst demonstrates improved product selectivity, stability and catalyst life. The improved selectivity is evidenced by lower methane production, higher C5+ yield and increased olefin production.

  6. Separation of catalyst from Fischer-Tropsch slurry

    SciTech Connect

    White, C.M.; Quiring, M.S.; Jensen, K.L.; Hickey, R.F.; Gillham, L.D.

    1998-04-01

    This paper describes a process for the separation of catalysts used in Fischer-Tropsch synthesis. The separation is accomplished by extraction in which the organic compounds in the wax are dissolved and carried away from the insoluble inorganic catalyst particles that are primarily inorganic. The purified catalyst can be upgraded by various methods.

  7. Development and process evaluation of improved Fischer-Tropsch slurry catalysts. [Tenth] quarterly technical progress report, 1 January--31 March 1989

    SciTech Connect

    Withers, H.P.; Bukur, D.B.; Rosynek, M.P.

    1989-12-31

    The objective of this contract is to develop a consistent technical data base on the use of iron-based catalysts in Fischer-Tropsch (FT) synthesis reactions. This data base will be developed to allow the unambiguous comparison of the performance of these catalysts with each other and with state-of-the-art iron catalyst compositions. Particular attention will be devoted to generating reproducible kinetic and selectivity data and to developing reproducible improved catalyst compositions.

  8. Development and process evaluation of improved Fischer-Tropsch slurry catalysts. Sixth quarterly technical progress report, 1 January--31 March 1988

    SciTech Connect

    Withers, H.P.; Bukur, D.B.; Rosynek, M.P.

    1988-12-31

    The objective of this contract is to develop a consistent technical data base on the use of iron-based catalysts in Fischer-Tropsch (FT) synthesis reactions. This data base will be developed to allow the unambiguous comparison of the performance of these catalysts with each other and with state-of-the-art iron catalyst comparisons. Particular attention will be devoted to generating reproducible kinetic and selectivity data and to developing reproducible improved catalyst compositions.

  9. Separation of Fischer-Tropsch wax from catalyst using supercritical fluid extraction. Quarterly technical progress report, 1 January 1996--31 March 1996

    SciTech Connect

    Joyce, P.C.; Thies, M.C.

    1996-09-01

    The objective of this research project is to evaluate the potential of supercritical fluid extraction for separating the catalyst slurry of a Fischer-Tropsch (F-T) slurry bubble column (SBC) reactor into two fractions: (1) a catalyst-free wax containing less than 10 ppm particulate matter and (2) a concentrated catalyst slurry that is ready for recycle or regeneration. The wax will be extracted with a hydrocarbon solvent that has a critical temperature near the operating temperature of the SBC reactor, i.e., 200--300 {degrees}C. Initial work is being performed using n-hexane as the solvent. The success of the project depends on two major factors. First, the supercritical solvent must be able to dissolve the F-T wax; furthermore, this must be accomplished without entraining the solid catalyst. Second, the extraction must be controlled so as not to favor the removal of the low molecular weight wax compounds, i.e., a constant carbon-number distribution of the alkanes in the wax slurry must be maintained at steady-state column operation. During this quarter work focused on task 1b, experimental measurement of selected model systems. Vapor-liquid equilibrium experiments for the n- hexane/squalane system, which we initiated in the previous quarter, were continued and results are discussed in this report.

  10. Slurry phase Fischer-Tropsch synthesis: Cobalt plus a water-gas shift catalyst. [Quarterly] report, June 30, 1988--September 30, 1988

    SciTech Connect

    Yates, I.C.; Satterfield, C.N.

    1988-12-31

    This report details experiments performed on three different copper-based catalysts: Cu/Cr{sub 2}O{sub 3}, Cu/MnO/Cr{sub 2}O{sub 3} and Cu/ZnO/Al{sub 2}O{sub 3}. Of these three catalysts, the Cu/ZnO/Al{sub 2}O{sub 3} exhibits the greatest stability when slurried in octacosane. More than 1000 hours-on-stream indicate that the catalyst activity is not detrimentally affected by high pressure, high H{sub 2}/CO ratio, or the presence of alkenes. All of these are necessary stability characteristics for the water-gas shift catalyst, if it is to be used in combination with a cobalt Fischer-Tropsch catalyst. A review of documented reduction procedures for cobalt-based Fischer-Tropsch catalysts is presented.

  11. Fischer-Tropsch synthesis process employing a moderated ruthenium catalyst

    DOEpatents

    Abrevaya, Hayim

    1990-01-01

    A Fischer-Tropsch type process produces hydrocarbons from carbon monoxide and hydrogen using a novel catalyst comprising moderated ruthenium on an inorganic oxide support. The preferred moderator is silicon. Preferably the moderator is effectively positioned in relationship to ruthenium particles through simultaneous placement on the support using reverse micelle impregnation.

  12. Fischer-Tropsch synthesis process employing a moderated ruthenium catalyst

    DOEpatents

    Abrevaya, H.

    1990-07-31

    A Fischer-Tropsch type process produces hydrocarbons from carbon monoxide and hydrogen using a novel catalyst comprising moderated ruthenium on an inorganic oxide support. The preferred moderator is silicon. Preferably the moderator is effectively positioned in relationship to ruthenium particles through simultaneous placement on the support using reverse micelle impregnation. 1 fig.

  13. Fischer-Tropsch Catalyst for Aviation Fuel Production

    NASA Technical Reports Server (NTRS)

    DeLaRee, Ana B.; Best, Lauren M.; Bradford, Robyn L.; Gonzalez-Arroyo, Richard; Hepp, Aloysius F.

    2012-01-01

    As the oil supply declines, there is a greater need for cleaner alternative fuels. There will undoubtedly be a shift from crude oil to nonpetroleum sources as a feedstock for aviation (and other transportation) fuels. The Fischer-Tropsch process uses a gas mixture of carbon monoxide and hydrogen which is converted into various liquid hydrocarbons; this versatile gas-to-liquid technology produces a complex product stream of paraffins, olefins, and oxygenated compounds such as alcohols and aldehydes. The Fischer-Tropsch process can produce a cleaner diesel oil fraction with a high cetane number (typically above 70) without any sulfur and aromatic compounds. It is most commonly catalyzed by cobalt supported on alumina, silica, or titania or unsupported alloyed iron powders. Cobalt is typically used more often than iron, in that cobalt is a longer-active catalyst, has lower water-gas shift activity, and lower yield of modified products. Promoters are valuable in improving Fischer-Tropsch catalyst as they can increase cobalt oxide dispersion, enhance the reduction of cobalt oxide to the active metal phase, stabilize a high metal surface area, and improve mechanical properties. Our goal is to build up the specificity of the Fischer-Tropsch catalyst while adding less-costly transition metals as promoters; the more common promoters used in Fischer-Tropsch synthesis are rhenium, platinum, and ruthenium. In this report we will describe our preliminary efforts to design and produce catalyst materials to achieve our goal of preferentially producing C8 to C18 paraffin compounds in the NASA Glenn Research Center Gas-To-Liquid processing plant. Efforts at NASA Glenn Research Center for producing green fuels using non-petroleum feedstocks support both the Sub-sonic Fixed Wing program of Fundamental Aeronautics and the In Situ Resource Utilization program of the Exploration Technology Development and Demonstration program.

  14. Fischer-Tropsch Catalyst for Aviation Fuel Production

    NASA Technical Reports Server (NTRS)

    deLaRee, Ana B.; Best, Lauren M.; Hepp, Aloysius F.

    2011-01-01

    As the oil supply declines, there is a greater need for cleaner alternative fuels. There will undoubtedly be a shift from crude oil to non-petroleum sources as a feedstock for aviation (and other transportation) fuels. The Fischer-Tropsch process uses a gas mixture of carbon monoxide and hydrogen which is converted into various liquid hydrocarbons; this versatile gas-to-liquid technology produces a complex product stream of paraffins, olefins, and oxygenated compounds such as alcohols and aldehydes. The Fischer-Tropsch process can produce a cleaner diesel oil fraction with a high cetane number (typically above 70) without any sulfur and aromatic compounds. It is most commonly catalyzed by cobalt supported on alumina, silica, or titania or unsupported alloyed iron powders. Cobalt is typically used more often than iron, in that cobalt is a longer-active catalyst, has lower water-gas shift activity, and lower yield of modified products. Promoters are valuable in improving Fischer-Tropsch catalyst as they can increase cobalt oxide dispersion, enhance the reduction of cobalt oxide to the active metal phase, stabilize a high metal surface area, and improve mechanical properties. Our goal is to build up the specificity of the Fischer-Tropsch catalyst while adding less-costly transition metals as promoters; the more common promoters used in Fischer-Tropsch synthesis are rhenium, platinum, and ruthenium. In this report we will describe our preliminary efforts to design and produce catalyst materials to achieve our goal of preferentially producing C8 to C18 paraffin compounds in the NASA Glenn Research Center Gas-To-Liquid processing plant. Efforts at NASA Glenn Research Center for producing green fuels using non-petroleum feedstocks support both the Sub-sonic Fixed Wing program of Fundamental Aeronautics and the In Situ Resource Utilization program of the Exploration Technology Development and Demonstration program.

  15. Slurry phase Fischer-Tropsch synthesis: Cobalt plus a water-gas shift catalyst. [Quarterly] report, October 1, 1989--December 31, 1989

    SciTech Connect

    Yates, I.C.; Satterfield, C.N.

    1989-12-31

    The rate of synthesis gas consumption over a cobalt FischerTropsch catalyst was measured in a well-mixed, continuous-flow, slurry reactor at 220 to 240{degrees}C, 0.5 to 1.5 MPa, H{sub 2}/CO feed ratios of 1.5 to 3.5 and conversions of 7 to 68% of hydrogen and 11 to 73% of carbon monoxide. The inhibiting effect of carbon monoxide was determined quantitatively and a Langmuir-Hinshelwood-type equation of the following form was found to best represent the results: -R{sub H{sub 2+Co}} = (a P{sub CO}P{sub H{sub 2}})/(1 + b P{sub CO}){sup 2}. The apparent activation energy was 93 to 95 kJ/mol. Data from previous studies on cobalt-based Fischer-Tropsch catalysts are also well correlated with this rate expression.

  16. Surface characterization of iron Fischer-Tropsch catalysts

    SciTech Connect

    Kuivila, C.S.; Butt, J.B.; Stair, P.C.

    1986-01-01

    In this paper the authors address XPS characterization of the iron phases associated with Fischer-Tropsch catalysts. Results obtained for single-phase metal, oxide, and carbide samples are presented. Methods for estimating the extent of carbide formation during low conversion synthesis, and the extent of catalyst oxidation at high conversions are illustrated. This approach is used to monitor the evolution of an initially reduced, unsupported iron catalyst during synthesis at low conversion levels.

  17. Novel Fischer-Tropsch slurry catalysts and process concepts for selective transportation fuel production: Quarterly technical progress report, 1 July 1985-30 September 1985

    SciTech Connect

    Carroll, W.E.; Cilen, N.; Motika, S.A.; Withers, H.P. Jr.

    1987-09-01

    Four catalysts were prepared. Silica was examined as a support for the standard Co/sub 2/(CO)/sub 8//Zr(OPr)/sub 4/ composition. A mixed Co/Fe catalyst on zirconated silica was prepared from Co/sub 2/(CO)/sub 8/ and Fe/sub 3/(CO)/sub 12/, rather than from the (FeCo/sub 3/(CO)/sub 12/)/sup -/ anion. The use of Ti in place of Zr as the promoter was examined with the silica support. Further work on alternate supports was completed with the preparation of Co/sub 2/(CO)/sub 8/ and Zr(OPr)/sub 4/ on MgO 3.6SiO/sub 2/. Gas-phase screening was completed on three catalysts during the quarter. The effect of increasing the cobalt loading from 4 to 11 wt % for the Co/Zr/Al/sub 2/O/sub 3/ composition was to improve the bulk activity but lower the specific activity and to slightly shift the hydrocarbon selectivity to higher molecular weight products. The use of silica as a support for the mixed Co/Fe catalyst also provided an improvement in the Fischer-Tropsch activity but did not enhance the water-gas shift activity. Three catalysts were screened in the slurry reactor. A kinetic data analysis program was developed to aid in the analysis of catalyst data from the laboratory reactor tests operating at steady state. The required specifications include reaction stoichiometry and kinetics, the necessary reactor operating parameters, inlet conditions and gas phase product concentrations. Options include choice of fixing or fitting kinetic parameters and regressing rate coefficients in a normalized or standard fashion. Data from the catalyst slurry screening tests and more importantly the extended tests will be routinely analyzed for kinetic correlations. 5 refs., 50 figs., 105 tabs.

  18. Separation of catalyst from Fischer-Tropsch slurry

    DOEpatents

    White, Curt M.; Quiring, Michael S.; Jensen, Karen L.; Hickey, Richard F.; Gillham, Larry D.

    1998-10-27

    In a catalytic process for converting synthesis gas including hydrogen and carbon monoxide to hydrocarbons and oxygenates by a slurry Fischer-Tropsch synthesis, the wax product along with dispersed catalyst is removed from the slurry and purified by removing substantially all of the catalyst prior to upgrading the wax and returning a portion to the Fischer-Tropsch reaction. Separation of the catalyst particles from the wax product is accomplished by dense gas and/or liquid extraction in which the organic compounds in the wax are dissolved and carried away from the insoluble inorganic catalyst particles that are primarily inorganic in nature. The purified catalyst free wax product can be subsequently upgraded by various methods such as hydrogenation, isomerization, hydrocracking, conversion to gasoline and other products over ZSM-5 aluminosilicate zeolite, etc. The catalyst particles are returned to the Fischer-Tropsch Reactor by slurring them with a wax fraction of appropriate molecular weight, boiling point and viscosity to avoid reactor gelation.

  19. Separation of catalyst from Fischer-Tropsch slurry

    DOEpatents

    White, C.M.; Quiring, M.S.; Jensen, K.L.; Hickey, R.F.; Gillham, L.D.

    1998-10-27

    In a catalytic process for converting synthesis gas including hydrogen and carbon monoxide to hydrocarbons and oxygenates by a slurry Fischer-Tropsch synthesis, the wax product along with dispersed catalyst is removed from the slurry and purified by removing substantially all of the catalyst prior to upgrading the wax and returning a portion to the Fischer-Tropsch reaction. Separation of the catalyst particles from the wax product is accomplished by dense gas and/or liquid extraction in which the organic compounds in the wax are dissolved and carried away from the insoluble inorganic catalyst particles that are primarily inorganic in nature. The purified catalyst-free wax product can be subsequently upgraded by various methods such as hydrogenation, isomerization, hydrocracking, conversion to gasoline and other products over ZSM-5 aluminosilicate zeolite, etc. The catalyst particles are returned to the Fischer-Tropsch Reactor by mixing them with a wax fraction of appropriate molecular weight, boiling point and viscosity to avoid reactor gelation. 2 figs.

  20. Technology development for iron and cobalt Fischer-Tropsch catalysts

    SciTech Connect

    Davis, B.H.

    1999-11-01

    The impact of deuterium on the Fischer-Tropsch (FT) synthesis was studied with a precipitated iron catalyst in the slurry phase. Deuterium has been used by several research groups to better understand the mechanism of CO hydrogenation. Inverse (k{sub H}/k{sub D} < 1), normal (k{sub H}/k{sub D} > 1) and no isotope effect (k{sub H}/k{sub D} = 1) have been reported. The conflicting results are thought to arise because rate of reaction is a combination of kinetic and equilibrium factors. In summary, the presence of boron produced only minor changes on the properties of the cobalt catalyst. In earlier studies, it was shown that the presence of boron made the catalyst less susceptible to poisoning by sulfur. Steady-state supercritical Fischer-Tropsch synthesis was studied in the work using a fixed-bed reactor and an unpromoted Co/SiO{sub 2} catalyst. This serves as the baseline for promoted catalyst studies. A pentane-hexane mixture was used as the supercritical solvent. Overall reactor pressure, syngas partial pressure and contact time were kept constant to obtain a valid comparison of the impact of solvent density in the catalytic activity and selectivity. Three different partial pressures of the mixture were chosen based on the density-pressure curve in order to investigate the pressure tuning effect to Fischer-Tropsch synthesis near critical region.

  1. The role of zeolite in the Fischer-Tropsch synthesis over cobalt-zeolite catalysts

    NASA Astrophysics Data System (ADS)

    Sineva, L. V.; Asalieva, E. Yu; Mordkovich, V. Z.

    2015-11-01

    The review deals with the specifics of the Fischer-Tropsch synthesis for the one-stage syncrude production from CO and H2 in the presence of cobalt-zeolite catalytic systems. Different types of bifunctional catalysts (hybrid, composite) combining a Fischer-Tropsch catalyst and zeolite are reviewed. Special attention focuses on the mechanisms of transformations of hydrocarbons produced in the Fischer-Tropsch process on zeolite acid sites under the synthesis conditions. The bibliography includes 142 references.

  2. Supported fischer-tropsch catalyst and method of making the catalyst

    DOEpatents

    Dyer, Paul N.; Pierantozzi, Ronald; Withers, Howard P.

    1987-01-01

    A Fischer-Tropsch catalyst and a method of making the catalyst for a Fischer-Tropsch process utilizing the catalyst by which synthesis gas, particularly carbon-monoxide rich synthesis gas, is selectively converted to higher hydrocarbons of relatively narrow carbon number range is disclosed. In general, the selective and notably stable catalyst, consist of an inert carrier first treated with a Group IV B metal compound (such as zirconium or titanium), preferably an alkoxide compound, and subsequently treated with an organic compound of a Fischer-Tropsch metal catalyst, such as cobalt, iron or ruthenium carbonyl. Reactions with air and water and calcination are specifically avoided in the catalyst preparation procedure.

  3. Moessbauer spectroscopy studies of iron-catalysts used in Fischer-Tropsch (FT) processes. Quarterly technical progress report, October 1, 1996--December 31, 1996

    SciTech Connect

    Huffman, G.P.; Rao, K.R.P.M.

    1996-12-31

    The U.S. Department of Energy has currently a program to develop Fischer-Tropsch catalysts which are active at low H{sub 2}/Co ratio of 0.67. The Center for Applied Energy Research, University of Kentucky and Texas A&M University have been developing Fischer- Tropsch catalysts which are active at a low H{sub 2}/Co ratio of 0.67. It is of interest to find out any relationships that may exist between the iron phases that are produced during activation and FT synthesis and the activity of the catalysts. Moessbauer spectroscopy investigations were carried out on 32 iron-base catalysts during the period under review. Eleven catalysts withdrawn from slurry type of reactors during and at the end of FT synthesis were received from the University of Kentucky. Twenty one catalysts withdrawn at the end of the run from both the slurry and fixed-bed reactors were received from Texas A&M University.

  4. Slurry phase Fischer-Tropsch synthesis: Cobalt plus a water-gas shift catalyst. [Quarterly] report, July 1, 1990--September 30, 1990

    SciTech Connect

    Chanenchuk, C.A.; Yates, I.C.; Satterfield, C.N.

    1990-12-31

    A Co/MgO/SiO{sub 2} Fischer-Tropsch catalyst was operated simultaneously with a Cu/ZnO/Al{sub 2}O{sub 3} water-gas-shift catalyst in a slurry reactor for over 400 hours. The process conditions were held constant at a temperature of 240{degrees}C, a pressure of 0.79 MPa, and a 1.1 H{sub 2}/CO feed of 0.065 Nl/min-g.cat. The Fischer-Tropsch activity remained constant at the level predicted by the operation of the Co/MgO/SiO{sub 2} catalyst alone. The water-gas-shift reaction was near equilibrium. The hydrocarbon product distribution of the combined catalyst system was stable and matched that of the CO/MgO/SiO{sub 2} operating alone under similar conditions. The combined catalyst system exhibited a high selectivity to n-alkanes. Neither catalysts`s operation appeared to have a detrimental effect on that of the other, showing promise for future option.

  5. Catalyst and reactor development for a liquid phase Fischer-Tropsch process. Quarterly technical progress report, 1 October-31 December 1980

    SciTech Connect

    Brockington, J.W.; Dyer, P.N.; Pierantozzi, R.; Bauer, J.V.

    1981-01-01

    Air Products, under contract to the DOE, has begun a three year program in Catalyst and Reactor Development for a Liquid Phase Fischer-Tropsch Process. The program contains four major tasks: (1) Project Work Plan, (2) Slurry Catalyst Development, (3) Slurry Reactor Design Studies, and (4) Pilot Facility Design. Task 1 has been completed with the preparation of a Project Work Plan describing in detail the methods and technical approach to be used. Task 2 has four sub-tasks. The first segment of the background studies deals with the effect of metal particle size on product selectivity and is included in this report. Based on these background studies, ten of twenty modified traditional Fischer-Tropsch catalysts to be prepared and slurry phase tested have been identified. Slurry reactor specifications have been finalized and a comprehensive product analysis scheme and data handling system has been established. Forty of the fifty supported metal cluster catalysts to be prepared and gas phase screened have been identified. Two metal cluster catalysts have been prepared. A detailed experimental plan for the first phase of Task 3 using a 5-inch diameter cold flow reactor simulator has been completed.

  6. Separation of Fischer-Tropsch wax from catalyst using supercritical fluid extraction. Quarterly technical progress report, July 1, 1995--September 31, 1995

    SciTech Connect

    Thies, M.C.; Joyce, P.C.

    1996-02-01

    Programming and testing of the highly complex Statistical Associating Fluid Theory (or SAFT) equation of state is essentially complete. As an accuracy check, results from our program were compared and found to be in excellent agreement with those of two other research groups (one in the US and two in Europe) for both a nonassociating (methane-hexadecane) and an associating (carbon dioxide-methanol) system. This equation is being used to model the solubility our model Fischer-Tropsch compounds in supercritical solvents such as hexane. SAFT has been chosen for this work because of its fundamental rigor. Therefore, extension of our model compound results to the poorly defined Fischer-Tropsch waxes should be more successful compared to more empirical equations such as Peng-Robinson. Computer-controlled automation of one of our dynamic supercritical fluid (SCF) extraction apparatus is complete. The apparatus collects samples automatically, dramatically reducing operator manpower and fatigue, and is also capable of controlling the operating pressure more precisely (i.e., within {plus_minus}2 psi). This apparatus (SFE I) will be used for future experiments with actual Fischer-Tropsch waxes. Modification/construction of another apparatus (SCF II) that will be used for our model component-SCF phase equilibria/solubility studies is nearly complete; it is currently being leak-tested. This apparatus was built to handle the low mass flow rates that will be required when measuring solubility data for the more expensive model compounds, such as n-C40. Anticipated results for the next quarter include VLE measurements for hexane-squalane at temperatures to 573 K.

  7. TECHNOLOGY DEVELOPMENT FOR IRON AND COBALT FISCHER-TROPSCH CATALYSTS

    SciTech Connect

    Burtron H. Davis

    1999-01-30

    The effects of copper on Fischer-Tropsch activity, selectivity and water-gas shift activity were studied over a wide range of syngas conversion. Three catalyst compositions were prepared for this study: (a) 100Fe/4.6Si/1.4K, (b) 100Fe/4.6Si/0.10Cu/1.4K and (c) 100Fe/4.6Si/2.0Cu/1.4K. The results are reported in Task 2. The literature review for cobalt catalysts is approximately 90% complete. Due to the size of the document, it has been submitted as a separate report labeled Task 6.

  8. TECHNOLOGY DEVELOPMENT FOR IRON FISCHER-TROPSCH CATALYSTS

    SciTech Connect

    Davis, B.H.

    1998-07-22

    The goal of the proposed work described in this Final Report was the development of iron-based Fischer-Tropsch catalysts that combined high activity, selectivity and life with physical robustness for slurry phase reactors that will produce either low-alpha or high-alpha products. The work described here has optimized the catalyst composition and pretreatment operation for a low-alpha catalyst. In parallel, work has been conducted to design a high-alpha iron catalyst that is suitable for slurry phase synthesis. Studies have been conducted to define the chemical phases present at various stages of the pretreatment and synthesis stages and to define the course of these changes. The oxidation/reduction cycles that are anticipated to occur in large, commercial reactors have been studied at the laboratory scale. Catalyst performance has been determined for catalysts synthesized in this program for activity, selectivity and aging characteristics.

  9. Polymer bound Fischer-Tropsch catalysts

    SciTech Connect

    Hsu, W.-L.; Kurr, R.J.; Maly, N.A.; Parker, D.K.; Stozier, R.W.

    1986-06-24

    A process is described for the conversion of synthesis gas to hydrocarbons which comprises contacting the synthesis gas with a catalyst in the vapor phase at a temperature from 175/sup 0/C to 300/sup 0/C and a pressure of at least 1000 kPa. The improvement described here comprising using as the catalyst a catalyst.

  10. The surface chemistry of iron Fischer-Tropsch catalysts

    SciTech Connect

    Dwyer, D.J.; Hardenburgh, J.H.

    1986-04-01

    The indirect conversion of coal to liquid hydrocarbons via steam gasification followed by synthesis gas (CO/H/sub 2/) chemistry has been the subject of intensive study for a number of decades. A key technological challenge facing researchers in this area is control over the product distribution during the hydrocarbon synthesis step. In the case of iron Fischer-Tropsch catalysts, it has been known that the addition of alkali to the metal catalyst has a significant impact on the product distribution. Iron catalysts treated with alkali produce less methane more alkenes and higher molecular weight products. In spite of numerous investigations, the details of this promotional effect are not understood on a molecular level. To explore the role of alkali in the surface chemistry of iron catalysts, the authors have carried out a combined surface science and catalytic kinetic study of a model iron catalyst with and without surface alkali.

  11. Technology development for iron Fischer-Tropsch catalysts. Quarterly technical progress report for period ending December 1993

    SciTech Connect

    O`Brien, R.J.; Xu, Liguang; Bi, Xiangxin; Eklund, P.; Davis, B.H.

    1993-12-31

    Conversion data as a function of time of synthesis for the two catalysts are shown in Figures 2 and 3. In general the precipitated catalyst is more active than the iron carbide catalyst with syn-gas conversions starting at 80% as compared to 50% for the latter; however, both catalysts deactivated with increasing reaction time. A comparison of the C{sub 2}, C{sub 3} and C{sub 4} olefin selectivities at 26% CO conversion (precipitated catalyst-336 hr of synthesis, iron carbide catalyst-122 hr of synthesis) are shown in Figure 4. Surprisingly the precipitated catalyst had a higher olefin content than the iron carbide catalyst. It has been reported that a similar iron carbide catalyst has higher selectivity for the production of olefins than a ``conventionally prepared`` Fe/Co catalyst. The discrepancy may be due in part to comparing the olefin selectivity of the two catalysts at different conversions. Their ``conventional catalyst`` had a C{sub 2}{minus}C{sub 4} olefin content of 37% at 72% conversion compared to 86% olefin at 55% conversion for the iron carbide catalyst. In general the olefin selectivity of a catalyst is highest at low conversions. The iron carbide catalyst of this study produces more hydrocarbons than the precipitated catalyst; furthermore, it produces a higher fraction of C{sub 3} + (86% vs. 84%) and C{sub 5}+ (67% vs. 61%) hydrocarbons (Figure 5). Correspondingly, the iron carbide catalyst produces less methane and ethane than the precipitated catalyst (Figure 6). These hydrocarbon and C{sub 5}+ selectivities are similar to those reported earlier.

  12. Development of improved iron Fischer-Tropsch catalysts. Quarterly technical progress report, January 1, 1993--March 31, 1993

    SciTech Connect

    Bukur, D.B.

    1993-04-20

    The objective of proposed research is the development of catalysts with enhanced slurry phase activity and better selectivity to fuel range products, through a more detailed understanding and systematic studies of the effects of pretreatment procedures and promoters/binders (silica) on catalyst performance. Studies of both supported and unsupported iron/copper/potassium catalysts are presented.

  13. Development of improved iron Fischer-Tropsch catalysts. Quarterly technical progress report, April 1, 1993--June 31, 1993

    SciTech Connect

    Bukur, D.B.

    1993-07-15

    The objective of proposed research is the development of catalysts with enhanced slurry phase activity and better selectivity to fuel range products, through a more detailed understanding and systematic studies of the effects of pretreatment procedures and promoters/binders (silica) on catalyst performance. Studies of both supported and unsupported iron/copper/potassium catalysts are presented.

  14. Development of improved iron Fischer-Tropsch catalysts. Quarterly technical progress report, October 1, 1992--December 31, 1992

    SciTech Connect

    Bukur, D.B.

    1993-01-29

    The objective of proposed research is the development of catalysts with enhanced slurry phase activity and better selectivity to fuel range products, through a more detailed understanding and systematic studies of the effects of pretreatment procedures and promoters/binders (silica) on catalyst performance. Studies of both supported and unsupported iron/copper/potassium catalysts are presented.

  15. Development of improved iron Fischer-Tropsch catalysts. Quarterly technical progress report, April 1, 1992--June 30, 1992

    SciTech Connect

    Bukur, D.B.

    1992-07-15

    The objective of proposed research is the development of catalysts with enhanced slurry phase activity and better selectivity to fuel range products, through a more detailed understanding and systematic studies of the effects of pretreatment procedures and promoters/binders (silica) on catalyst performance. Studies of both supported and unsupported iron/copper/potassium catalysts are presented.

  16. Development of improved iron Fischer-Tropsch catalysts. Quarterly technical progress report, July 1, 1992--September 30, 1992

    SciTech Connect

    Bukur, D.B.

    1992-10-23

    The objective of proposed research is the development of catalysts with enhanced slurry phase activity and better selectivity to fuel range products, through a more detailed understanding and systematic studies of the effects of pretreatment procedures and promoters/binders (silica) on catalyst performance. Studies of both supported and unsupported iron/copper/potassium catalysts are presented.

  17. Development of improved iron Fischer-Tropsch catalysts. Quarterly technical progress report, July 1, 1993--September 30, 1993

    SciTech Connect

    Bukur, D.B.

    1993-10-21

    The objective of proposed research is the development of catalysts with enhanced slurry phase activity and better selectivity to fuel range products, through a more detailed understanding and systematic studies of the effects of pretreatment procedures and promoters/binders (silica) on catalyst performance. Studies of both supported and unsupported iron/copper/potassium catalysts are presented.

  18. Development of precipitated iron Fischer-Tropsch catalysts. Quarterly technical progress report for the period July 1, 1996--September 30, 1996

    SciTech Connect

    Bukur, D.B.

    1996-12-02

    Two slurry reactor tests were completed in continuation of our studies on the effect of pretreatment conditions on catalyst reactivity and selectivity. Exceptionally good performance was obtained in run SA-2186, using the new pretreatment developed at Texas A&M University. The work on catalyst characterization by temperature programmed and isothermal reduction on a variety of iron catalysts, with different amounts of promoters, has been continued. These studies are complementing our work on pretreatment effect research, and provide additional insights into the effect of pretreatment procedures on the reduction behavior of iron catalysts. The overall objectives are to: (1) demonstrate repeatability of performance and preparation procedure of two high activity, high alpha iron Fischer-Tropsch catalysts synthesized at Texas A&M University; (2) seek potential improvements in the catalysts performance through variation in process condition, pretreatment procedures and/or modifications in catalyst synthesis; (3) investigate performance of catalysts in a small bubble column slurry reactor; and (4) investigate feasibility of producing catalysts on a large scale in collaboration with a catalyst manufacturer.

  19. Fischer-Tropsch cobalt catalyst development

    SciTech Connect

    Oukaci, R.; Goodwin, J.G. Jr.; Marcelin, G.; Singleton, A.

    1994-12-31

    Based on the information provided in patents assigned to Gulf, Shell, Exxon, and Statoil, a series of catalysts has been prepared consisting of 12-20 wt% cobalt, a second metal promoter (Ru or Re), and an oxide promoter such as lanthana, zirconia, or alkali oxide, the support being alumina, silica, or titania. All catalysts have been extensively characterized by different methods. The catalysts have been evaluated in terms of their activity, selectivity both in a fixed bed reactor and in a slurry bubble column reactor, and the results correlated with their physico-chemical properties.

  20. Development and process evaluation of improved Fischer-Tropsch slurry catalysts: Quarterly technical progress report, 1 July-30 September 1987

    SciTech Connect

    Withers, H.P.; Bukur, D.B.; Rosynek, M.P.

    1987-12-21

    Nine runs in fixed bed reactors were performed during this period using the precipitated iron catalysts prepared in our laboratory. These tests were made to investigate the effect of copper and potassium promoters on catalyst activity and selectivity at various process conditions. Catalysts with 0 and 0.05 parts potassium were less stable and less active than catalysts with higher potassium loadings. Potassium and copper also influence product selectivity. One additional run was also made with United Catalyst, Inc. fused iron catalyst as a repeat of a previous run. The investigation of catalyst activation/reduction procedures was begun in this period. The reductant type, temperature and pressure of the reduction will be studied as parameters, using a 100 Fe/3.0 Cu/0.2 K catalyst. Surface area and pore size distribution measurements have been continued for the doubly promoted catalysts. Temperature programmed reduction (TPR) has also been applied to the doubly promoted catalysts. The effects of copper and potassium on catalyst reduction are similar to those observed for singly promoted catalysts. Work on isothermal reduction tests has also been performed. The promotional effect of copper on iron reduction is also seen at isothermal conditions, in agreement with the TPR results. Also, it was found that isothermal CO reduction occurs more rapidly than with H/sub 2/. The trapping scheme of both fixed bed reactors and the existing slurry reactor have been modified to allow for the high pressure collection of products. Improvements in the temperature control of the fixed bed reactors have been made. A new slurry reactor, including a computer data acquisition/control system, has been built. The preliminary tests of this system have been completed. 7 refs., 29 figs., 16 tabs.

  1. Slurry phase Fischer-Tropsch synthesis: Cobalt plus a water-gas shift catalyst. [Quarterly] report, October 1, 1988--December 31, 1988

    SciTech Connect

    Yates, I.C.; Satterfield, C.N.

    1988-12-31

    A cobalt Fischer-Tropsch catalyst (CO/MgO/silica) was reduced and slurried in combination with reduced Cu/ZnO/Al{sub 2}0{sub 3} water-gas-shift catalyst. Combined catalyst system was run at fixed process conditions for more than 400 hours. The system showed stable selectivity. The Cu/ZnO/Al{sub 2}0{sub 3} water-gas-shift catalyst remained reasonably active in the presence of the cobalt catalyst. Hydrocarbon selectivity of the cobalt and Cu/ZnO/Al{sub 2}0{sub 3} catalyst system compared favorably to selectivity of iron-based catalysts. Methane selectivity was slightly higher for the cobalt-based system, but C{sub 5}{sup +} selectivity was essentially the same. The hydrocarbon product distribution appeared to exhibit a double-a behavior. a{sub 1} was near 0.80 which is higher than that of iron catalysts, while a{sub 2} was calculated to be 0.86 which is somewhat lower than would be typical for an iron-based catalyst.

  2. Development of improved iron Fischer-Tropsch catalysts. Quarterly technical progress report, 1 July 1990--30 September 1990

    SciTech Connect

    Bukur, D.B.

    1990-10-29

    The objective of proposed research is development of catalysts with enhanced slurry phase activity and better selectivity to fuel range products, through a more detailed understanding and systematic studies of the effects of pretreatment procedures and promoters/binders (silica) on catalyst performance.

  3. Development of improved iron Fischer-Tropsch catalysts. Quarterly technical progress report, 1 April 1991--30 June 1991

    SciTech Connect

    Bukur, D.B.

    1991-07-19

    The objective of proposed research is development of catalysts with enhanced slurry phase activity and better selectivity to fuel range products, through a more detailed understanding and systematic studies of the effects of pretreatment procedures and promoters/binders (silica) on catalyst performance.

  4. Development of improved iron Fischer-Tropsch catalysts. Quarterly technical progress report, 1 October 1990--31 December 1990

    SciTech Connect

    Bukur, D.B.

    1991-01-25

    The objective of proposed research is development of catalysts with enhanced slurry phase activity and better selectivity to fuel range products, through a more detailed understanding and systematic studies of the effects of pretreatment procedures and promoters/binders (silica) on catalyst performance.

  5. Development of improved iron Fischer-Tropsch catalysts. Quarterly technical progress report, 1 July 1991--30 September 1991

    SciTech Connect

    Bukur, D.B.

    1991-10-28

    The objective of proposed research is development of catalysts with enhanced slurry phase activity and better selectivity to fuel range products, through a more detailed understanding and systematic studies of the effects of pretreatment procedures and promoters/binders (silica) on catalyst performance.

  6. Development of improved iron Fischer-Tropsch catalysts. Quarterly technical progress report, 1 January 1991--31 March 1991

    SciTech Connect

    Bukur, D.B.

    1991-04-24

    The objective of proposed research is development of catalysts with enhanced slurry phase activity and better selectivity to fuel range products, through a more detailed understanding and systematic studies of the effects of pretreatment procedures and promoters/binders (silica) on catalyst performance.

  7. Development of improved iron Fischer-Tropsch catalysts. Quarterly technical progress report, 1 April 1990--30 June 1990

    SciTech Connect

    Bukur, D.B.

    1990-06-17

    The objective of proposed research is development of catalysts with enhanced slurry phase activity and better selectivity to fuel range products, through a more detailed understanding and systematic studies of the effects of pretreatment procedures and promoters/binders (silica) on catalyst performance.

  8. Development of improved iron Fischer-Tropsch catalysts. Quarterly technical progress report, 1 January 1990--31 March 1990

    SciTech Connect

    Bukur, D.B.; Patel, S.A.; Dalai, A.K.; Jayanthi, G.; Ledakowicz, S.

    1990-04-30

    The objective of proposed research is development of catalysts with enhanced slurry phase activity and better selectivity to fuel range products, through a more detailed understanding and systematic studies of the effects of pretreatment procedures and promoters/binders (silica) on catalyst performance.

  9. Development of improved iron Fischer-Tropsch catalysts. Quarterly technical progress report, 1 October 1991--31 December 1991

    SciTech Connect

    Bukur, D.B.

    1992-01-10

    The objective of proposed research is development of catalysts with enhanced slurry phase activity and better selectivity to fuel range products, through a more detailed understanding and systematic studies of the effects of pretreatment procedures and promoters/binders (silica) on catalyst performance.

  10. Development of improved iron Fischer-Tropsch catalysts. Quarterly technical progress report, 1 October 1989--31 December 1989

    SciTech Connect

    Bukur, D.B.; Patel, S.A.

    1990-01-15

    The objective of proposed research is development of catalysts with enhanced slurry phase activity and better selectivity to fuel range products, through a more detailed understanding and systematic studies of the effects of pretreatment procedures and promoters/binders (silica) on catalyst performance.

  11. Development of precipitated iron Fischer-Tropsch catalysts. Quarterly technical progress report, 1 January 1995--31 March 1995

    SciTech Connect

    Bukur, D.B.; Lang, X.; Reddy, B.

    1995-05-23

    During the reporting period we completed synthesis of about 100 g of catalyst with nominal composition 100 Fe/3 Cu/4 K/16 SiO{sub 2} (S-3416-2), and of another batch (173 g) of the same catalyst (S-3416-3). Also, we synthesized two additional batches of catalyst with nominal composition 100 Fe/5 Cu/6 K/24 SiO{sub 2}, in the amounts of 240 g (S-5624-3) and 200 g (S-5624-4). These amounts are sufficient for all planned tests with these two catalysts for the entire duration of this contract. The synthesized catalysts were characterized by atomic absorption, and BET surface area and pore size distribution measurements.

  12. Technology development for iron Fischer-Tropsch catalysts

    SciTech Connect

    Frame, R.R.; Abrevaya, H.; Gala, H.B.

    1991-01-01

    The objectives of this contract are to develop a technology for the production of active and stable iron Fischer-Tropsch catalysts for use in slurry-phase synthesis reactors and to develop a scale up procedure for large-scale synthesis of such catalysts for process development and long-term testing in slurry bubble-column reactors. The catalyst performance target in the slurry bubble-column reactor is 88% CO + H{sub 2} conversion at a minimum space velocity of 2.4 NL/hr/gFe. Typical feed used to attain this level of conversion is preferred to have H{sub 2} and CO in the molar ratio of 0.5 to 1.0. The desired sum of methane and ethane selectivities is no more than 4%, and the conversion loss per week is not to exceed 1%.

  13. Technology development for iron Fischer-Tropsch catalysts

    SciTech Connect

    Not Available

    1991-01-01

    The objectives of this contract are to develop a technology for the production of active and stable iron Fischer-Tropsch catalysts for use in slurry-phase synthesis reactors and to develop a scaleup procedure for large-scale synthesis of such catalyst for process development and long-term testing in slurry bubble-column reactors. With a feed containing H{sub 2} and CO in the molar ratio of 0.5 to 1.0, the catalyst performance target in the slurry bubble-column reactor is 88% CO + H{sub 2} conversion at a minimum space velocity of 2.4 NL/hr/gFe. The desired sum of methane and ethane selectivities is no more than 4%, and the conversion loss per week is not to exceed 1%.

  14. Technology development for iron Fischer-Tropsch catalysts

    SciTech Connect

    Not Available

    1990-01-01

    The objectives of this contract are to develop a technology for the production of active and stable iron Fischer-Tropsch catalysts for use in slurry-phase synthesis reactors and to develop a scale-up procedure for large-scale synthesis of such catalysts for process development and long-term testing in slurry bubble column reactors. With a feed containing H{sub 2}:CO in the ratio of 0.5 to 1.0, the catalyst performance target in the slurry bubble column reactor is 88% CO + H{sub 2}conversion at a minimum space velocity of 2.4 NL/h/gFe. The methane + ethane selectivity is desired to be no more than 4% and the conversion loss per week is not to exceed 1%.

  15. Moessbauer spectroscopy studies of iron-catalysts used in Fischer-Tropsch (FT) processes. Quarterly technical progress report, January--March, 1995

    SciTech Connect

    Huffman, G.P.; Rao, K.R.P.M.

    1995-10-01

    Moessbauer spectroscopy investigations were carried out on 14 iron-based catalysts during the period under review. The catalyst 100Fe/4.4Si/0.71K (all atomic ratios) was subjected to activation first in syngas and subsequently in CO gas atmosphere. Fischer-Tropsch (FT) synthesis was carried out on the above catalyst. Another catalyst 100Fe/4.4Si/2.6Cu/0.71K (all atomic ratios) activated in syngas and subjected to FT synthesis was also studied to understand the effect of added Cu on the phase distribution and its effect on the FT activity. The following trends were observed: (1) activation of the catalyst in syngas, H{sub 2}/CO, lead to the formation of Fe{sub 3}O{sub 4} and no carbides were formed, the FT activity was found to be low at 9--12% (H{sub 2}+CO) conversion; (2) activation of the catalyst in CO for 22hrs lead to the formation of 33% of {chi}-carbide and the FT activity was found to be high at 88% maximum; (3) addition of copper to the catalyst has improved the FT activity for those catalysts pretreated in syngas at elevated pressures.

  16. Iron Fischer-Tropsch catalysis: Properties of an ultrafine iron oxide catalyst. Quarterly progress report, July--September 1992

    SciTech Connect

    Xu, Liguang; Bao, Shiqi; O`Brien, R.; Houpt, D.; Davis, B.H.

    1992-12-31

    A commercial Fe oxide with a particle size of 3 nm is now available. The FT requires considerable time on stream before steady state conditions are attained. Since it is desirable to obtain FT data for the smaller ultrafine Fe oxide catalysts at larger times on steam, data for operation up to 6 months were collected using slurry phase. Results show that the ultrafine Fe oxide maintain catalytic activity for a 150-day operating period. Addition of 0.5% K increased the activity; after 56 days, the activity had declined to and below that of unpromoted catalyst. Neither the unpromoted nor K-promoted catalyst exhibited good selectivity for alkenes.

  17. Development of precipitated iron Fischer-Tropsch catalysts. Quarterly technical progress report, 1 July 1995--30 September 1995

    SciTech Connect

    Bukur, D.B.

    1995-12-20

    The following accomplishments were made on task 4. Reproducibility of Catalyst Preparation: (1) Five slurry reactor tests were completed. Three tests were conducted using catalyst C (100 Fe/3 Cu/4 K/16 SiO{sub 2}) from three different batches (runs SB-2695, SB-2145 and SA-2715), and two tests were conducted with catalyst B (100 Fe/5 Cu/6 K/24 SiO{sub 2}) from two different preparation batches (runs SA-2615 and SB-2585). Performance of catalysts from different batches (activity, selectivity and deactivation rates) was similar to that of catalysts from the original batch (synthesized during DOE Contract DE- AC22-89PC89868). Thus, another major objective of the present contract, demonstration of reproducibility of catalyst preparation procedure and performance, has been accomplished. With these tests the work on Task 4 has been successfully completed. Two fixed bed reactor tests of catalysts B and C synthesized using potassium silicate solution as the source of potassium promoter were completed during this period (Task 5. The Effect of Source of Potassium and Basic Oxide Promoter). Activity of catalysts prepared using potassium silicate as the source of potassium promotion was somewhat higher, and their methane selectivities were higher than those of the corresponding catalysts prepared by incipient wetness impregnation using KHCO{sub 3} as the source of potassium promoter. However, these differences were not large, and may have been caused by experimental artifacts (e.g. existence of local hot spots in a reactor). A slurry reactor test (SA-2405) of catalyst with nominal composition 100 Fe/5 Cu/2 Ca/24 SiO{sub 2} was completed (Task 5). In general, the catalyst activity, space-time-yield, and hydrocarbon selectivities in this run during testing at:260{degrees}C, 2.17 MPa (300 psig), 2-2.6 Nl/g-cat/h and H{sub 2}CO=0.67 were quite good, and comparable to the best results obtained in our Laboratory.

  18. Development of improved iron Fischer-Tropsch catalysts. Quarterly technical progress report, 1 January 1992--31 March 1992

    SciTech Connect

    Bukur, D.B.

    1992-04-24

    Three tests (two fixed bed and one stirred tank slurry reactor) were completed during the reporting period. Also, the work on catalyst characterization by different techniques (atomic absorption, BET surface area and pore size distribution and x-ray powder diffraction).The performance of a precipitated iron catalyst with nominal composition lOOFe/0.3Cu/0.8K has been evaluated in two fixed bed reactor tests designated FB-0142 and FB-0352 following pretreatment with syngas (H{sub 2}/CO=0.67) at 280{degree}C, 3Nl/g-cat/h and atomspheric pressure for 8 hours. Flow interruption occurred in the first test (FB-0142) at about 72h on stream, and the second test (FB-0352) was to assess any potential adverse effects of this flow interruption on performance of the catalyst. The catalyst was tested at 250{degree}C, 200 psig, 2Nl/g-cat/h using syngas of the same composition as that employed during the pretreatment. Initial conversions in both tests were high (about 84%) but the catalyst deactivated fairly rapidly. The (H{sub 2} + CO) conversion at the end of the first test (120h on stream) was about 52%, whereas the syngas conversion at the end of the second test (150h) was about 55%, indicating that the brief flow interruption during test FB-0142 had resulted in higher deactivation rate. Hydrocarbon selectivities in both tests were similar and their average values werr: (CH{sub 4})=4.7, (C{sub 2}{minus}C{sub 4})=19.5, (C{sub 5}{minus}C{sub 11})=25.3 and C{sub 12}{sup +}=50.5 wt%.

  19. Fischer-tropsch synthesis in supercritical fluids. Quarterly technical progress report, October 1, 1994--December 21, 1994

    SciTech Connect

    Akgerman, A.; Bukur, D.B.

    1995-01-31

    Progress reports are presented for the following two tasks: (1) diffusion coefficients of F-T products in supercritical fluids; and (2) Fischer-Tropsch reaction related studies. The objectives for this quarter for task 1 were to measure molecular diffusion coefficients and effective diffusivities at the same conditions. The objectives for task 2 were to conduct two additional tests with the Ruhrchemie catalyst and a catalyst synthesized in our laboratory under supercritical conditions.

  20. Iron on mixed zirconia-titania substrate Fischer-Tropsch catalyst and method of making same

    DOEpatents

    Dyer, Paul N.; Nordquist, Andrew F.; Pierantozzi, Ronald

    1986-01-01

    A Fischer-Tropsch catalyst comprising iron co-deposited with or deposited on particles comprising a mixture of zirconia and titania, preferably formed by co-precipitation of compounds convertible to zirconia and titania, such as zirconium and titanium alkoxide. The invention also comprises the method of making this catalyst and an improved Fischer-Tropsch reaction process in which the catalyst is utilized.

  1. Separation of Fischer-Tropsch wax from catalyst using supercritical fluid extraction. Quarterly technical progress report, April 1, 1996--June 30, 1996

    SciTech Connect

    Joyce, P.C.; Thies, M.C.

    1996-11-01

    The objective of this research project is to evaluate the potential of SCF extraction for separating the catalyst slurry of a Fischer- Tropsch (F-T) slurry bubble column (SBC) reactor into two fractions: (1) a catalyst-free wax containing less than 10 ppm particulate matter and (2) a concentrated catalyst slurry that is ready for recycle or regeneration. The wax will be extracted with a hydrocarbon solvent that has a critical temperature near the operating temperature of the SBC reactor, i.e., 200-300{degrees}C. Initial work is being performed using n-hexane as the solvent. The success of the project depends on two major factors. First, the supercritical solvent must be able to dissolve the F-T wax; furthermore, this must be accomplished without entraining the solid catalyst. Second, the extraction must be controlled so as not to favor the removal of the low molecular weight wax compounds, i.e., a constant carbon-number distribution of the alkanes in the wax slurry must be maintained at steady-state column operation. To implement our objectives, the following task structure is being implemented: Task 1 equilibrium solubility measurements; Task 2 thermodynamic modeling; and Task 3 process design studies. Progress reports are presented for each task.

  2. Improved Fischer-Tropsch Synthesis catalysts for indirect coal liquefaction

    SciTech Connect

    Tong, G.T.; Wilson, R.B.; McCarty, J.G.

    1987-01-01

    The monoruthenium cluster catalyst with a molecular sieve support and the tetraruthenium cluster catalyst with a sodium-Y zeolite support have been examined for Fischer-Tropsch Synthesis (FTS) performance at high pressure (6.9 MPa) in a slurry reactor and compared with conventional ruthenium with an alumina support and clean fused iron catalysts. Of the four catalysts tested, only the conventional ruthenium catalyst exhibited a chain growth factor of 0.88 and a methane selectivity of 6.6%, which are typical of slurry reactor results reported for iron catalysts under similar conditions. The other three catalysts tested showed low chain growth factors (ranging from 0.44 to 0.57) and high methane selectivity (ranging from 20 to 32%). A cobalt catalyst with approximately 50% sulfur coverage was prepared and tested for FTS activity and selectivity at ambient pressure and compared with the FTS performance of the clean and fully sulfided cobalt catalysts. The introduction of sulfur caused a decrease in methane selectivity and an increase in olefin selectivity with only a moderate decline in activity. 1 ref., 2 tabs.

  3. Catalyst and reactor development for a liquid-phase Fischer-Tropsch process. Quarterly technical progress report, 1 January 1982-31 March 1982

    SciTech Connect

    Dyer, P. N.; Pierantozzi, R.; Brian, B. W.; Bauer, J. V.

    1982-04-01

    This report describes work on Catalyst and Reactor Development for a Liquid Phase Fischer-Tropsch Process. The program contains four major tasks: (1) Project Work Plan, (2) Slurry Catalyst Development, (3) Slurry Reactor Design Studies, and (4) Pilot Facility Design. Two modified conventional catalysts were screened in the gas phase, and the improved results gave directions for further development work. Three slurry tests were run. The first, a 15 wt % slurry of a coprecipitated catalyst, showed non-standard Schulz-Flory product distributions, with a significant increase in C/sub 9/+ hydrocarbons. The second, a 19 wt % slurry of a support catalyst, also showed large deviations from the standard Schulz-Flory product, with a high selectivity for C/sub 10/-C/sub 25/ hydrocarbons. Compared to a previous gas phase test, however, CH/sub 4/ yields were higher and the activity lower. A third slurry test of a supported cluster catalyst also showed a lower activity than in the gas phase. Oil analysis indicates that the reduction of activity observed for supported metal catalysts in the slurry compared to the gas phase may be due to poisoning by an oil component. An alternative oil will therefore be utilized for future tests. Seven supported cluster catalysts were synthesized and six were screened in the gas phase. In two cases, an increased yield of C/sub 10/+ products was observed, dependent upon the reaction conditions. Another showed a product selectivity that could be shifted between oxygenates and hydrocarbons. Gas hold-up and solids dispersion measurements in the 5'' column were completed for the 0 to 5 ..mu..m and 45 to 53 ..mu..m iron oxide/isoparaffin, and the 45 to 53 ..mu..m and 90 to 115 ..mu..m silica/isoparaffin systems. The gas hold-up results were correlated by statistical analysis.

  4. ATTRITION RESISTANT IRON-BASED FISCHER-TROPSCH CATALYSTS

    SciTech Connect

    K. Jothimurugesan; James G. Goodwin, Jr.; Santosh K. Gangwal

    1999-10-01

    Fischer-Tropsch (FT) synthesis to convert syngas (CO + H{sub 2}) derived from natural gas or coal to liquid fuels and wax is a well-established technology. For low H{sub 2} to CO ratio syngas produced from CO{sub 2} reforming of natural gas or from gasification of coal, the use of Fe catalysts is attractive because of their high water gas shift activity in addition to their high FT activity. Fe catalysts are also attractive due to their low cost and low methane selectivity. Because of the highly exothermic nature of the FT reaction, there has been a recent move away from fixed-bed reactors toward the development of slurry bubble column reactors (SBCRs) that employ 30 to 90 {micro}m catalyst particles suspended in a waxy liquid for efficient heat removal. However, the use of FeFT catalysts in an SBCR has been problematic due to severe catalyst attrition resulting in fines that plug the filter employed to separate the catalyst from the waxy product. Fe catalysts can undergo attrition in SBCRs not only due to vigorous movement and collisions but also due to phase changes that occur during activation and reaction.

  5. Technology development for iron Fischer-Tropsch catalysts

    SciTech Connect

    O`Brien, R.J.; Raje, A.; Keogh, R.A.

    1995-12-31

    The objective of this research project is to develop the technology for the production of physically robust iron-based Fischer-Tropsch catalysts that have suitable activity, selectivity and stability to be used in the slurry phase synthesis reactor development. The catalysts that are developed shall be suitable for testing in the Advanced Fuels Development Facility at LaPorte, Texas, to produce either low-or high-alpha product distributions. Previous work by the offeror has produced a catalyst formulation that is 1.5 times as active as the {open_quotes}standard-catalyst{close_quotes} developed by German workers for slurry phase synthesis. In parallel, work will be conducted to design a high-alpha iron catalyst this is suitable for slurry phase synthesis. Studies will be conducted to define the chemical phases present at various stages of the pretreatment and synthesis stages and to define the course of these changes. The oxidation/reduction cycles that are anticipated to occur in large, commercial reactors will be studied at the laboratory scale. Catalyst performance will be determined for catalysts synthesized in this program for activity, selectivity and aging characteristics.

  6. Technology development for iron Fischer-Tropsch catalysts

    SciTech Connect

    Frame, R.R.

    1991-01-01

    Objectives are to develop active, stable iron Fischer-Tropsch catalysts for use in slurry-phase synthesis reactors and to develop a scaleup procedure for large-scale synthesis of such catalysts for process development and long-term testing in slurry bubble-column reactors. For a H[sub 2]-CO in molar ratio of 0.5 to 1.0, catalyst performance target is 88% CO+H[sub 2] conversion at a minimum space velocity of 2.4 NL/hr/gFe, with no more than 4% methane/ethane selectivity and 1% conversion loss per week. During this period, it was found that the performance of the slurry-phase iron and copper oxide-based catalyst depends on the amount of K. Five catalysts with differing K contents were studied. The catalysts with the lowest K were more active than the ones with higher K levels. The one with the middle K level was judged best.

  7. TECHNOLOGY DEVELOPMENT FOR IRON AND COBALT FISCHER-TROPSCH CATALYSTS

    SciTech Connect

    Burtron H. Davis

    1999-04-30

    The impact of activation procedure on the phase composition of precipitated iron Fischer-Tropsch (FT) catalysts has been studied. Catalyst samples taken during activation and FT synthesis have been characterized by Moessbauer spectroscopy. Formation of iron carbide is necessary for high FT activity. Hydrogen activation of precipitated iron catalysts results in reduction to predominantly metallic iron and Fe{sub 3}O{sub 4}. Metallic iron is not stable under FT 3 4 conditions and is rapidly converted to {epsilon}{prime}-Fe{sub 2.2}C. Activation with carbon monoxide or syngas 2.2 with low hydrogen partial pressure reduces catalysts to {chi}-Fe{sub 5}C{sub 2} and a small amount of 5 2 superparamagnetic carbide. Exposure to FT conditions partially oxidizes iron carbide to Fe{sub 3}O{sub 4}; however, catalysts promoted with potassium or potassium and copper maintain a constant carbide content and activity after the initial oxidation. An unpromoted iron catalyst which was activated with carbon monoxide to produce 94% {chi}-Fe{sub 5}C{sub 2}, deactivated rapidly as the carbide was oxidized to Fe{sub 3}O{sub 4}. No difference in activity, stability or deactivation rate was found for {chi}-Fe{sub 5}C{sub 2} and {epsilon}{prime}-Fe{sub 2.2}C.

  8. Catalyst and reactor development for a liquid-phase Fischer-Tropsch process. Quarterly technical progress report, 1 January 1983-31 March 1983

    SciTech Connect

    Dyer, P.N.; Pierantozzi, R.; Brian, B.W.; Nordquist, A.F.; Parsons, R.L.

    1983-09-01

    Two major tasks continued in the APCI/US DOE contract, Catalysts and Reactor Development for a Liquid Phase Fischer-Tropsch Process: (1) Slurry Catalyst Development; and (2) Slurry Reactor Design Studies. The first extended slurry test was continued using a proprietary catalyst. The results showed that it was possible to produce yields in the diesel fuel region equal to or greater than the Schulz-Flory maximum, without further optimization. Low deactivation rates were observed. Kinetic rate constants were derived from the CSTR experiments, and used in a computer simulation to predict conversions from bubble column operation under Rheinpreussen conditions. Short term (21 day) slurry tests were carried out on two other catalysts, optimized by the screening program. Parametric gas phase screening results were concluded for two additional modified conventional catalysts, and the optimum preparation and activation methods for diesel fuel selectively were chosen. In the hydrodynamic studies, work in the 5'' column was completed with measurements on the Fe/sub 2/O/sub 3//water slurries. In the 12'' column, fitted with 7 heat transfer tubes, hydrodynamic parameters were determined for slurries of Fe/sub 2/O/sub 3/ in paraffin and water, and SiO/sub 2/ in water. Gas holdups were close to the Akita and Yoshida correlation for the hydrocarbon slurries, but lower for the aqueous ones. Solid concentration profiles, modelled by the sedimentation model, gave evidence of particle agglomeration in SiO/sub 2//hydrocarbon slurries, underlining the need to use chemically similar slurries in cold-flow modelling work. In the 5'' column, solid and liquid dispersion coefficients were found to be equal.

  9. Improved Fischer-Tropsch catalysts for indirect coal liquefaction

    SciTech Connect

    Wilson, R.B. Jr.; Tong, G.T.; Chan, Y.W.; Huang, H.W.; McCarty, J.G.

    1989-02-01

    The Fischer-Tropsch synthesis (FTS)reaction is the established technology for the production of liquid fuels from coal by an indirect route using coal-derived syngas (CO + H{sub 2}). Modern FTS catalysts are potassium- and copper-promoted iron preparations. These catalysts exhibit moderate activity with carbon monoxide-rich feedstocks such as the syngas produced by advanced coal gasification processes. However, the relatively large yields of by-product methane and high-molecular-weight hydrocarbon waxes detract from the production of desired liquid products in the C{sub 5}-C{sub 16} range needed for motor and aviation fuel. The goal of this program is to decrease undesirable portions of the FTS hydrocarbon yield by altering the Schultz-Flory polymerization product distribution through design and formulation of improved catalysts. Two approaches were taken: (1) reducing the yield of high-molecular-weight hydrocarbon waxes by using highly dispersed catalysts produced from surface-confined multiatomic clusters on acid supports and (2) suppressing methane production by uniformly pretreating active, selective conventional FTS catalysts with submonolayer levels of sulfur.

  10. The development of a selective ruthenium Fischer-Tropsch catalyst

    SciTech Connect

    Abrevaya, H.

    1989-01-01

    A new stable Fischer-Tropsch catalyst with very high selectivity to distillate fuels and with low light ends production was developed. This catalyst, which was made by a reverse micelle technique, contains 2.8% (by weight) ruthenium in the form of 4--6 nm particles on alumina and a proprietary modifier. The new modified ruthenium catalyst did not noticeably deactivate during 814 hours at about 80% CO conversion, 2H{sub 2}:1 CO feed ratio, 208{degree}C at inlet, 62 atm and 150 gas hourly space velocity. In order to determine the catalyst's tolerance, the operational severity was increased between 814 hours and 1700 hours by increasing the temperature and space velocity to 225{degree}C at inlet and to 205 hr{sup {minus}1}, respectively. A deactivation rate of about 0.016%/hour was measured under these more severe conditions at about 70% conversion level. These results with the new modified ruthenium catalyst compare favorably with those reported for the two commercial Sasol processes. The Arge process makes approximately 38% distillate fuel with 14--18% light ends, while the Synthol process makes about 48% distillate with 38% light ends. 82 refs., 360 figs., 66 tabs.

  11. Separation of Fischer-Tropsch wax from catalyst using supercritical fluid extraction. Quarterly technical progress report, 1 October 1995--31 December 1995

    SciTech Connect

    Thies, M.C.; Joyce, P.C.

    1996-06-01

    The objective of this research project is to evaluate the potential of supercritical fluid (SCF) extraction for separating the catalyst slurry of a Fischer-Tropsch slurry bubble column (SBC) reactor into two fractions: (1) a catalyst-free wax containing less than 10 ppm particulate matter and (2) a concentrated catalyst slurry that is ready for recycle or regeneration. The wax will be extracted with a hydrocarbon solvent that has a critical temperature near the operating temperature of the SBC reactor, i.e., 200-300{degrees}C. Initial work is being performed using n-hexane as the solvent. During the reporting period, work on the small-scale, continuous-flow apparatus continued. Initial experiments have been performed on a binary mixture of n-hexane (solvent) and squalane (model compound) at 200{degrees}C. A total of fifteen samples were collected at 135, 160, and 208 psig, with pressures being controlled to within {plus_minus}2 psi. Results indicate that the equilibrium phase compositions can in principle be measured to a reproducibility of {plus_minus}0.5% in the squalane-rich bottomphase and {plus_minus}2% in the hexane-rich top phase, with respect to the minor component. However, other data measured at these same conditions at another time exhibited scatter that was as much as 5 times greater. We believe that improvements in (1) the method of preheating the feed to the view cell/phase separator and to (2) the sample collection technique are required before data of high accuracy can consistently be generated. The apparatus modifications required to effect these improvements are currently underway and should be completed by the middle of February.

  12. Fischer-Tropsch Synthesis on ALD-synthesized Catalysts

    NASA Astrophysics Data System (ADS)

    Van Norman, Staci A.

    Cobalt catalysts were prepared on porous Al2O 3 and W/Al2O3 supports by atomic layer deposition (ALD) that used sequential reactions of cobaltocene (CoCp2) and H 2 at 483 to 523 K. This preparation method avoided formation of an intermediate oxide, so the catalysts could be activated at lower temperatures. Some of these catalysts had CO reaction rates per g of Co in Fischer-Tropsch synthesis (FTS) that were three times those reported for Co catalysts prepared by incipient wetness. The FTS reacts CO and H2 to form hydrocarbon liquids that can used as synthetic fuels. The rate of FTS depended on the number of ALD cycles, and catalysts prepared with one cycle had activities equivalent to incipient wetness Co catalysts; the highest reaction rate per g of catalyst was obtained for catalysts prepared using four ALD cycles. Two types of Co were observed on the alumina surface using TEM: Co particles with diameters between 0.6 and 1.8 nm (75% were smaller than 1 nm), and Co crystalline planes that were as large as 35 nm. Cobalt catalysts prepared by ALD retained adsorbed ligands that appeared to be stable for at least eight months at room temperature. Tungsten was deposited onto porous Al2O 3 by ALD to provide a catalyst support with higher thermal conductivity because the FTS reaction is highly exothermic. The W indeed increased thermal conductivity, and the resulting supports were used for Co ALD following deposition of an Al2O3 ALD layer. However, although Co deposits on ALD Al2O3, the Co had no activity for FTS, apparently because the ALD Al2O3 was amorphous. In contrast ALD Al 2O3 that was heat treated at high temperature was partially crystalline and served as a support for an active FTS catalyst.

  13. Attrition Resistant Iron-Based Fischer-Tropsch Catalysts

    SciTech Connect

    Jothimurugesan, K.; Goodwin, J.G.; Spivey, J.J.; Gangwal, S.K.

    1997-03-26

    The Fischer-Tropsch (F-T) reaction provides a way of converting coal-derived synthesis gas (CO+H{sub 2}) to liquid fuels. Since the reaction is highly exothermic, one of the major problems in control of the reaction is heat removal. Recent work has shown that the use of slurry bubble column reactors (SBCRS) can largely solve this problem. Iron-based (Fe) catalysts are preferred catalysts for F-T when using low CO/H{sub 2} ratio synthesis gases derived from modem coal gasifiers. This is because in addition to reasonable F-T activity, the FT catalysts also possess high water gas shift (WGS) activity. However, a serious problem with the use of Fe catalysts in a SBCR is their tendency to undergo attrition. This can cause fouling/plugging of downstream filters and equipment, making the separation of catalyst from the oil/wax product very difficult if not impossible, and results in a steady loss of catalyst from the reactor. The objectives of this research are to develop a better understanding of the parameters affecting attrition resistance of Fe F-T catalysts suitable for use in SBCRs and to incorporate this understanding into the design of novel Fe catalysts having superior attrition resistance. Catalyst preparations will be based on the use of spray drying and will be scalable using commercially available equipment. The research will employ among other measurements, attrition testing and F-T synthesis, including long duration slurry reactor runs in order to ascertain the degree of success of the various preparations. The goal is to develop an Fe catalyst which can be used in a SBCR having only an internal filter for separation of the catalyst from the liquid product, without sacrificing F-T activity and selectivity.

  14. Attrition Resistant Iron-Based Fischer-Tropsch Catalysts.

    SciTech Connect

    Jothimurugesan, K.; Goodwin, J.S.; Spivey, J.J.; Gangwal, S.K.

    1997-09-22

    The Fischer-Tropsch (F-T) reaction provides a way of converting coal-derived synthesis gas (CO and H{sub 2}) to liquid fuels. Since the reaction is highly exothermic, one of the major problems in control of the reaction is heat removal. Recent work has shown that the use of slurry bubble column reactors (SBCRs) can largely solve this problem. Iron-based (Fe) catalysts are preferred catalysts for F-T when using low CO/H{sub 2} ratio synthesis gases derived from modern coal gasifiers. This is because in addition to reasonable F-T activity, the F-T catalysts also possess high water gas shift (WGS) activity. However, a serious problem with the use of Fe catalysts in a SBCR is their tendency to undergo attrition. This can cause fouling/plugging of downstream filters and equipment, making the separation of catalyst from the oil/wax product very difficult if not impossible, and results in a steady loss of catalyst from the reactor. The objectives of this research are to develop a better understanding of the parameters affecting attrition resistance of Fe F-T catalysts suitable for use in SBCRs and to incorporate this understanding into the design of novel Fe catalysts having superior attrition resistance. Catalyst preparations will be based on the use of spray drying and will be scalable using commercially available equipment. The research will employ among other measurements, attrition testing and F-T synthesis, including long duration slurry reactor runs in order to ascertain the degree of success of the various preparations. The goal is to develop an Fe catalyst which can be used in a SBCR having only an internal filter for separation of the catalyst from the liquid product, without sacrificing F-T activity and selectivity.

  15. ATTRITION RESISTANT IRON-BASED FISCHER-TROPSCH CATALYSTS

    SciTech Connect

    James G. Goodwin, Jr.; James J. Spivey; K. Jothimurugesan; Santosh K. Gangwal

    1999-03-29

    The Fischer-Tropsch (F-T) reaction provides a way of converting coal-derived synthesis gas (CO+H{sub 2}) to liquid fuels. Since the reaction is highly exothermic, one of the major problems in control of the reaction is heat removal. Recent work has shown that the use of slurry bubble column reactors (SBCRs) can largely solve this problem. Iron-based (Fe) catalysts are preferred catalysts for F-T when using low CO/H2 ratio synthesis gases derived from modern coal gasifiers. This is because in addition to reasonable F-T activity, the F-T catalysts also possess high water gas shift (WGS) activity. However, a serious problem with the use of Fe catalysts in a SBCR is their tendency to undergo attrition. This can cause fouling/plugging of downstream filters and equipment, making the separation of catalyst from the oil/wax product very difficult if not impossible, and results in a steady loss of catalyst from the reactor. The objectives of this research are to develop a better understanding of the parameters affecting attrition resistance of Fe F-T catalysts suitable for use in SBCRs and to incorporate this understanding into the design of novel Fe catalysts having superior attrition resistance. Catalyst preparations will be based on the use of spray drying and will be scalable using commercially available equipment. The research will employ among other measurements, attrition testing and F-T synthesis, including long duration slurry reactor runs in order to ascertain the degree of success of the various preparations. The goal is to develop an Fe catalyst which can be used in a SBCR having only an internal filter for separation of the catalyst from the liquid product, without sacrificing F-T activity and selectivity. The effect of silica addition via coprecipitation and as a binder to a doubly promoted Fischer-Tropsch synthesis iron catalyst (100 Fe/5 Cu/4.2 K) was studied. The catalysts were prepared by coprecipitation, followed by binder addition and drying in a 1 m

  16. XPS characterization of iron Fischer-Tropsch catalysts

    SciTech Connect

    Kuivila, C.S.; Stair, P.C.; Butt, J.B.

    1986-04-01

    Analysis of Fe(2p) XPS and iron Auger spectra, combined with C(1s) XPS measurements, provides a valuable technique for studying the compositional behavior of Fischer-Tropsch catalysts. The extent of catalyst oxidation during synthesis at high conversions may be estimated in terms of the area contribution of oxide phases to the Fe(2p) spectrum. Similarities between the metal and carbide core level spectra are likely to complicate the determination of these phases when oxides are present. Analysis of the metal and carbide contributions to the iron Auger spectrum provides an alternate method for monitoring surface carbide formation during low conversion synthesis. The ''surface compositions'' obtained in this manner are at best semi-quantitative, since the contribution of a particular phase to the XPS or Auger spectrum will depend on both the amount and distribution of that phase within the detected volume. In spite of this, the spectrum fitting technique should prove to be useful in characterizing the time and conversion dependent nature of the active catalyst surface.

  17. Technology development for iron Fischer-Tropsch catalysis. Quarterly technical progress report, October--December, 1994

    SciTech Connect

    1994-12-31

    Fischer-Tropsch catalysts must undergo a pretreatment in order to be active. As part of the authors comprehensive study to maximize the activity of iron based precipitated Fischer-Tropsch catalysts, they are currently attempting to optimize the activation procedure. Although they are able to achieve high activity using CO pretreatment, the catalysts tend to deactivate suddenly and rapidly after 500 hr of synthesis. Kolbel reports high CO conversion comparable to these results at a lower gas flow (2.4 vs. 3.4 nL/hr-g(Fe)); however, he achieved greater stability with conversions reported to be 90% after 1,400 hrs. One possibility for Kolbel`s higher stability could be due to the activation procedure. Herein are reported the initial results of a study to optimize the catalyst composition and the operating conditions for the iron based slurry phase Fischer-Tropsch synthesis when synthesis gas activation is utilized.

  18. ATTRITION RESISTANT IRON-BASED FISCHER-TROPSCH CATALYSTS

    SciTech Connect

    JAMES G. GOODWIN, JR.; JAMES J. SPIVEY; K. JOTHIMURUGESAN; SANTOSH K. GANGWAL

    1998-09-17

    The Fischer-Tropsch (F-T) reaction provides a way of converting coal-derived synthesis gas (CO+H{sub 2}) to liquid fuels. Since the reaction is highly exothermic, one of the major problems in control of the reaction is heat removal. Recent work has shown that the use of slurry bubble column reactors (SBCRs) can largely solve this problem. Iron-based (Fe) catalysts are preferred catalysts for F-T when using low CO/H{sub 2} ratio synthesis gases derived from modern coal gasifiers. This is because in addition to reasonable F-T activity, the F-T catalysts also possess high water gas shift (WGS) activity. However, a serious problem with the use of Fe catalysts in a SBCR is their tendency to undergo attrition. This can cause fouling/plugging of downstream filters and equipment, making the separation of catalyst from the oil/wax product very difficult if not impossible, and results in a steady loss of catalyst from the reactor. The objectives of this research are to develop a better understanding of the parameters affecting attrition resistance of Fe F-T catalysts suitable for use in SBCRs and to incorporate this understanding into the design of novel Fe catalysts having superior attrition resistance. Catalyst preparations will be based on the use of spray drying and will be scalable using commercially available equipment. The research will employ among other measurements, attrition testing and F-T synthesis, including long duration slurry reactor runs in order to ascertain the degree of success of the various preparations. The goal is to develop an Fe catalyst which can be used in a SBCR having only an internal filter for separation of the catalyst from the liquid product, without sacrificing F-T activity and selectivity. The effect of silica addition via coprecipitation and as a binder to a doubly promoted Fischer-Tropsch synthesis iron catalyst (100 Fe/5 Cu/4.2 K) was studied. The catalysts were prepared by coprecipitation, followed by binder addition and drying in a 1

  19. The hydrocarbon selectivity of cobalt Fischer-Tropsch catalysts

    SciTech Connect

    Yates, I.C.; Satterfield, C.N.

    1991-07-01

    A cobalt Fischer-Tropsch catalyst was studied in a continuous-flow, well-stirred slurry reactor at 220 to 240{degrees}C, 0.5 to 1.5 MPa, H{sub 2}/CO feed ratios between 1.5 and 3.5, H{sub 2} conversions between 6 and 68%, and CO conversions between 11 and 73%. Increasing space velocity (decreasing conversion) or decreasing reactor H{sub 2}/CO ratio decreased the yield of (undesired) C{sub 1} products and increased the yield of (desired) C{sub 10}+ products. Reactor temperature and pressure had little effect on the carbon number distribution. These findings are interpreted in terms of the extent of the readsorption of 1-alkenes into growing chains on the catalyst surface. The relative selectivity to 1-alkenes by the primary synthesis and secondary reaction of l-alkenes to n-alkanes and 2-alkenes depends on reactor H{sub 2}/CO ratio and CO concentration. 25 refs., 15 figs.

  20. TECHNOLOGY DEVELOPMENT FOR IRON AND CONBALT FISCHER-TROPSCH CATALYSTS

    SciTech Connect

    Burtron H. Davis

    2000-10-01

    The use of alkali promoters has been widely practiced. However, data to compare various promoters is limited for the iron-based catalysts and much of the available data were obtained at low pressure or under a variety of reaction conditions. The importance of the alkali promoter in determining catalytic activity, stability and selectivity merits a comparison of the promoters under suitable reaction conditions. The present study utilizes medium pressure synthesis conditions to compare the alkali promoters under the same reaction conditions and over a wide range of conversion levels. Iron-based Fischer-Tropsch (FT) catalysts undergo a series of phase transformations during activation and use. Activation with carbon monoxide or syngas typically results in the conversion of Fe{sub 2}O{sub 3} to Fe{sub 3}O{sub 4} and ultimately to one or more carbides. During FT synthesis, iron carbides can be oxidized to Fe{sub 3}O{sub 4} if the H{sub 2}O/H{sub 2} or CO{sub 2}/CO ratios are high enough. There has been considerable debate about the active phase of the FT synthesis. Some studies have indicated an active oxide species while most have supported a carbide species. Moessbauer spectroscopy has proven to be an effective technique for the analysis of iron-based FT catalysts. In situ Moessbauer studies have been reported; however, these studies have been performed at low pressure and low conversions. Studies performed at industrially relevant conditions have generally involved removing the catalyst from the reactor followed by passivation which, if not performed properly, will oxidize the catalyst. Herein are reported the Moessbauer results obtained on an unpromoted precipitated iron catalyst that was activated and reacted in a slurry phase, continuous stirred tank reactor at high conversion and under industrially relevant conditions.

  1. The renaissance of iron-based Fischer-Tropsch synthesis: on the multifaceted catalyst deactivation behaviour.

    PubMed

    de Smit, Emiel; Weckhuysen, Bert M

    2008-12-01

    Iron-based Fischer-Tropsch catalysts, which are applied in the conversion of CO and H2 into longer hydrocarbon chains, are historically amongst the most intensively studied systems in heterogeneous catalysis. Despite this, fundamental understanding of the complex and dynamic chemistry of the iron-carbon-oxygen system and its implications for the rapid deactivation of the iron-based catalysts is still a developing field. Fischer-Tropsch catalysis is characterized by its multidisciplinary nature and therefore deals with a wide variety of fundamental chemical and physical problems. This critical review will summarize the current state of knowledge of the underlying mechanisms for the activation and eventual deactivation of iron-based Fischer-Tropsch catalysts and suggest systematic approaches for relating chemical identity to performance in next generation iron-based catalyst systems (210 references). PMID:19020686

  2. DEVELOPMENT OF PRECIPITATED IRON FISCHER-TROPSCH CATALYSTS

    SciTech Connect

    Dr. Dragomir B. Bukur; Dr. X. Lang; Dr. S. Chokkaram; Dr. L. Nowicki; G. Wei; Dr. Y. Ding; Dr. B. Reddy; Dr. S. Xiao

    1999-07-22

    Despite the current worldwide oil glut, the US will ultimately require large-scale production of liquid (transportation) fuels from coal. Slurry phase Fischer-Tropsch (F-T) technology, with its versatile product slate, may be expected to play a major role in production of transportation fuels via indirect coal liquefaction. Some of the F-T catalysts synthesized and tested at Texas A and M University under DOE Contract No. DE-AC22-89PC89868 were more active than any other known catalysts developed for maximizing production of high molecular weight hydrocarbons (waxes). The objectives of the present contract were to demonstrate repeatability of catalyst performance and reproducibility of preparation procedures of two of these catalysts on a laboratory scale. Improvements in the catalyst performance were attempted through the use of: (a) higher reaction pressure and gas space velocity to maximize the reactor productivity; (b) modifications in catalyst preparation steps; and (c) different pretreatment procedures. Repeatability of catalyst performance and reproducibility of catalyst synthesis procedure have been successfully demonstrated in stirred tank slurry reactor tests. Reactor space-time-yield was increased up to 48% by increasing reaction pressure from 1.48 MPa to 2.17 MPa, while maintaining the gas contact time and synthesis gas conversion at a constant value. Use of calcination temperatures above 300 C, additional CaO promoter, and/or potassium silicate as the source of potassium promoter, instead of potassium bicarbonate, did not result in improved catalyst performance. By using different catalyst activation procedures they were able to increase substantially the catalyst activity, while maintaining low methane and gaseous hydrocarbon selectivities. Catalyst productivity in runs SA-0946 and SA-2186 was 0.71 and 0.86 gHC/g-Fe/h, respectively, and this represents 45-75% improvement in productivity relative to that achieved in Rheinpreussen's demonstration plant

  3. Fischer-Tropsch slurry catalysts for selective transportation fuel production

    SciTech Connect

    Carroll, W.E.; Cilen, N.; Withers, H.P. Jr.

    1986-01-01

    The future use of coal as a source of conventional transportation fuel will depend on the development of an economical and energy efficient liquefaction process. Technologies that have been commercially proven or that are close to commercialization include the fixed- and fluidized-bed Fischer-Tropsch (FT) synthesis, methanol synthesis (fixed-bed and slurry-phase) and the Mobil methanol-to-gasoline process. Of these technologies, the Fischer-Tropsch hydrocarbon synthesis produces the widest slate of products and has been in operation for the longest period.

  4. Studying the fischer tropsch synthesis on alumina support cobalt base catalyst in fixed bed reactor

    NASA Astrophysics Data System (ADS)

    Oues, Adnan Khalil

    A Fischer-Tropsch catalyst composed of cobalt supported on alumina was prepared. This catalyst was cobalt/alumina (Co/AL2O3). The physical characterization of the catalyst was conducted using surface area analysis through the BET method, and particle size analysis. Fischer-Tropsch experiments were conducted in a fixed bed reactor. A flow rate of 100sml/min was selected based experimentally. Two temperatures were 330, and 350°C, and three different pressures as follows 145, 217.6, and 290 psig. The results were evaluated and studied based on conversion of hydrogen and carbon monoxide, in addition to selectivity of products.

  5. Low nitrogen iron-containing Fischer-Tropsch catalyst and conversion of synthesis gas therewith

    SciTech Connect

    Bell, W.K.; Haag, W.O.; Kirker, G.W.; Klocke, D.J.

    1987-08-11

    This patent describes a process for converting syngas to hydrocarbons comprising: (a) contacting an iron-containing Fischer-Tropsch catalyst with a syngas stream under conditions effective to achieve high conversion of the syngas to substantial amounts of C/sub 3//sup +/ carbon compounds; (b) contacting the effluent stream from (a) with a shape selective crystalline zeolite having a Constraint Index of about 1 to 12; and (c) recovering from the effluent stream of (b) gasoline and distillate materials; the improvement which comprises preparing the iron-containing Fischer-Tropsch catalyst by a process which continuously precipitates an aqueous solution containing iron nitrate with aqueous ammonia at a pH of about 6.5 to 6.9 and a temperature ranging from about 70/sup 0/ to 100/sup 0/C and thereafter washing the resulting precipitate with an aqueous wash solution to produce a Fischer-Tropsch catalyst containing less than about 500 ppm nitrogen.

  6. Fly ash zeolite catalyst support for Fischer-Tropsch synthesis

    NASA Astrophysics Data System (ADS)

    Campen, Adam

    This dissertation research aimed at evaluating a fly ash zeolite (FAZ) catalyst support for use in heterogeneous catalytic processes. Gas phase Fischer-Tropsch Synthesis (FTS) over a fixed-bed of the prepared catalyst/FAZ support was identified as an appropriate process for evaluation, by comparison with commercial catalyst supports (silica, alumina, and 13X). Fly ash, obtained from the Wabash River Generating Station, was first characterized using XRD, SEM/EDS, particle size, and nitrogen sorption techniques. Then, a parametric study of a two-step alkali fusion/hydrothermal treatment process for converting fly ash to zeolite frameworks was performed by varying the alkali fusion agent, agent:flyash ratio, fusion temperature, fused ash/water solution, aging time, and crystallization time. The optimal conditions for each were determined to be NaOH, 1.4 g NaOH: 1 g fly ash, 550 °C, 200 g/L, 12 hours, and 48 hours. This robust process was applied to the fly ash to obtain a faujasitic zeolite structure with increased crystallinity (40 %) and surface area (434 m2/g). Following the modification of fly ash to FAZ, ion exchange of H+ for Na+ and cobalt incipient wetness impregnation were used to prepare a FTS catalyst. FTS was performed on the catalysts at 250--300 °C, 300 psi, and with a syngas ratio H2:CO = 2. The HFAZ catalyst support loaded with 11 wt% cobalt resulted in a 75 % carbon selectivity for C5 -- C18 hydrocarbons, while methane and carbon dioxide were limited to 13 and 1 %, respectively. Catalyst characterization was performed by XRD, N2 sorption, TPR, and oxygen pulse titration to provide insight to the behavior of each catalyst. Overall, the HFAZ compared well with silica and 13X supports, and far exceeded the performance of the alumina support under the tested conditions. The successful completion of this research could add value to an underutilized waste product of coal combustion, in the form of catalyst supports in heterogeneous catalytic processes.

  7. Fischer Tropsch synthesis in supercritical fluids. Quarterly technical progress report, January 1, 1995--March 31, 1995

    SciTech Connect

    Akgerman, A.; Bukur, D.B.

    1996-05-01

    Our objectives for this quarter were: (1) to install and test the temperature probe and the flammable gas detector: (2) to conduct Fischer-Tropsch synthesis experiments at baseline conditions and at a high pressure in order to test the newly constructed fixed bed reactor assembly.

  8. Effect of potassium promotion on iron-based catalysts for Fischer-Tropsch synthesis

    SciTech Connect

    Raje, A.P.; O`Brien, R.J.; Davis, B.H.

    1998-11-15

    The effect of potassium on Fischer-Tropsch catalyst activity, kinetic parameters, and selectivity has been investigated for a precipitated iron catalyst that was employed with low H{sub 2}/CO ratio synthesis gas. A wide range of synthesis gas conversions have been obtained by varying space velocities over catalysts with various potassium loadings. Differing trends in catalyst activity with potassium loading were observed depending on the space velocity of synthesis gas conversion. As potassium loading increased, the catalyst activity either decreased (low conversion), passed through a maximum (intermediate conversion), or increased (high conversion). This is shown to be a result of the increasing dependency of the Fischer-Tropsch synthesis on the hydrogen formed by the water-gas shift reaction with increasing synthesis gas conversions. Both the rate constant and the adsorption parameter in a common two-parameter Fischer-Tropsch rate expression decreased with potassium loading; therefore, observed maxima in Fischer-Tropsch rate with potassium loading can be due to the opposing influences of these parameters. The effect of potassium on alkene selectivity was dependent on the number of carbon atoms of the hydrocarbons as well as the carbon monoxide conversion level. The extent of isomerization of 1-alkene product decreased with potassium loading, while the selectivity to methane decreased only slightly with increasing potassium content at CO conversions about 50% and higher.

  9. Fischer-Tropsch kinetic studies with cobalt-manganese oxide catalysts

    SciTech Connect

    Keyser, M.J.; Everson, R.C.; Espinoza, R.L.

    2000-01-01

    An investigation was undertaken to establish the reaction mechanism for the Fischer-Tropsch reaction, in the presence of the water-gas shift reaction, over a cobalt-manganese oxide catalyst under conditions favoring the formation of gaseous, liquid, and solid (waxes) hydrocarbons (210--250 C and 6--26 bar). A micro-fixed-bed reactor was used with a cobalt-manganese oxide catalyst prepared by a coprecipitation method. An integral reactor model involving both Fischer-Tropsch and water-gas shift reaction kinetics was used to describe the overall performance. Reaction rate equations based on Langmuir-Hinshelwood-Hougen-Watson models for the Fischer-Tropsch reaction (hydrocarbon forming) and empirical reaction rate equations for the water-gas shift reaction from the literature were tested. Different combinations of the reaction rate equation were evaluated with the aid of a nonlinear regression procedure. It was found that a reaction rate equation for the Fischer-Tropsch reaction based on the enolic theory performed slightly better than a reaction rate equation based on the carbide theory. Reaction rate constants for the cobalt-manganese oxide catalyst are reported, and it is concluded that this catalyst also behaves very much like iron-based catalysts.

  10. Processes and catalysts for conducting fischer-tropsch synthesis in a slurry bubble column reactor

    DOEpatents

    Singleton, Alan H.; Oukaci, Rachid; Goodwin, James G.

    1999-01-01

    Processes and catalysts for conducting Fischer-Tropsch synthesis in a slurry bubble column reactor (SBCR). One aspect of the invention involves the use of cobalt catalysts without noble metal promotion in an SBCR. Another aspect involves using palladium promoted cobalt catalysts in an SBCR. Methods for preparing noble metal promoted catalysts via totally aqueous impregnation and procedures for producing attrition resistant catalysts are also provided.

  11. Processes and catalysts for conducting Fischer-Tropsch synthesis in a slurry bubble column reactor

    DOEpatents

    Singleton, A.H.; Oukaci, R.; Goodwin, J.G.

    1999-08-17

    Processes and catalysts are disclosed for conducting Fischer-Tropsch synthesis in a slurry bubble column reactor (SBCR). One aspect of the invention involves the use of cobalt catalysts without noble metal promotion in an SBCR. Another aspect involves using palladium promoted cobalt catalysts in an SBCR. Methods for preparing noble metal promoted catalysts via totally aqueous impregnation and procedures for producing attrition resistant catalysts are also provided. 1 fig.

  12. Catalyst and reactor development for a liquid phase Fischer-Tropsch process. Quarterly technical progress report, 1 January-31 March 1984

    SciTech Connect

    Carroll, W.E.; Cilen, N.; Motika, S.A.

    1985-03-01

    In the fourteenth quarter work continued for two major tasks: (1) Slurry Catalyst Development, and (2) Proprietary Catalyst A Development. The proprietary catalyst A work is part of a contract modification, begun last quarter, to improve the activity and center the selectivity for diesel fuel products of this catalyst. The basis of this work stems from promising results during extended testing of this catalyst. Variation of catalyst pretreatment methods and promoter levels are intended. Slurry catalyst development - Parametric gas phase screening tests were concluded on a modified conventional catalyst and an optimum preparation and activation procedure chosen for diesel fuel selectivity. A short term (approx. = 21 day) slurry test of this catalyst exhibited appreciable activity, but poor selectivity for diesel fuel products. The selectivity varied strongly with CO/H/sub 2/ ratio, but even at CO/H/sub 2/ = 2.0, products were predominantly below C/sub 10/. Catalyst A development - Three tests were conducted this quarter to determine the effects of varying the promoter levels of catalyst A. In summary, the basecase catalyst composition of this catalyst remained to be the most selective for diesel fuel. In activity level, a catalyst A' out-performed the activity of all catalysts tested to date. Surface analysis studies are underway to aid in understanding these effects and in so doing, optimizing the promoter levels for maximum activity and diesel fuel selectivity. Gas phase screening tests were conducted on catalyst A to determine the effects of activation and pretreatment procedures on activity and product selectivity. In general, no appreciable differences in bulk activity and only slight differences in hydrocarbon distribution were observed in the three tests conducted.

  13. Development and process evaluation of improved Fischer-Tropsch slurry catalysts

    SciTech Connect

    Withers, H.P. ); Bukur, D.B.; Rosynek, M.P. )

    1989-01-01

    The objective of this contract is to develop a consistent technical data base on the use of iron-based catalysts in Fischer-Tropsch (FT) synthesis reactions. This data base will be developed to allow the unambiguous comparison of the performance of these catalysts with each other and with state-of-the-art iron catalyst compositions. Particular attention will be devoted to generating reproducible kinetic and selectivity data and to developing reproducible improved catalyst compositions.

  14. Mössbauer investigations of the Fe-Cu-Mn catalysts for Fischer-Tropsch synthesis

    NASA Astrophysics Data System (ADS)

    Spânu, Viorica; Filoti, G.; Ilie, Ioana; Zamfirescu, Elena

    1990-07-01

    In the selective process of the syngas conversion to synthetic gasoline a bifunctional catalytic system has to be used. It was obtained by combination a Fischer-Tropsch catalyst with the HZSM-5 zeolite. The phase compositions of the precursor and the fresh catalyst were established as well as the optimum thermal treatment. The catalyst was reduced in pure H2 or in a H2+CO mixture. The influence of the reduction and reaction conditions on the catalyst structure was investigated.

  15. Development of process evaluation of improved Fischer-Tropsch slurry catalysts

    SciTech Connect

    Withers, H.P. ); Bukur, D.B.; Rosynek, M.P. )

    1988-01-01

    The objective of this contract is to develop a consistent technical data base on the use of iron-based catalysts in Fischer-Tropsch (FT) synthesis reactions. This data base will be developed to allow the unambiguous comparison of the performance of these catalysts with each other and with state-of-the-art iron catalyst compositions. Particular attention will be devoted to generating reproducible kinetic and selectivity data and to developing reproducible improved catalyst compositions.

  16. Development and process evaluation of improved Fischer-Tropsch slurry catalysts

    SciTech Connect

    Withers, H.P. ); Bukur, D.B.; Rosynek, M.P. )

    1987-01-01

    The objective of this contract is to develop a consistent technical data base on the use of iron-based catalysts in Fischer-Tropsch (FT) synthesis reactions. This data base will be developed to allow the unambiguous comparison of the performance of these catalysts with each other and with state-of-the-art iron catalyst compositions. Particular attention will be devoted to generating reproducible kinetic and selectivity data and to developing reproducible improved catalyst compositions.

  17. Development and process evaluation of improved Fischer-Tropsch slurry catalysts

    SciTech Connect

    Withers, H.P. ); Bukur, D.B.; Rosynek, M.P. )

    1988-01-01

    The objective of this contract is to develop a consistent technical data base on the use of iron-based catalysts in Fischer-Tropsch (F-T) synthesis reactions. This data base will be developed to allow the unambiguous comparison of the performance of these catalysts with each other and with state-of-the-art iron catalyst compositions. Particular attention will be devoted to generating reproducible kinetic and selectivity data and to developing reproducible improved catalyst compositions.

  18. Development and process evaluation of improved Fischer-Tropsch slurry catalysts

    SciTech Connect

    Withers, H.P. ); Bukur, D.B.; Rosynek, M.P. )

    1988-01-01

    The objective of this contract is to develop a consistent technical data base on the use of iron-based catalysts in Fischer-Tropsch (FT) synthesis reactions. This data base will be developed to allow the unambiguous comparison of the performance of these catalysts with each other and with state-of-the-art iron catalyst comparisons. Particular attention will be devoted to generating reproducible kinetic and selectivity data and to developing reproducible improved catalyst compositions.

  19. Development and process evaluation of improved Fischer-Tropsch slurry catalysts

    SciTech Connect

    Withers, H.P. ); Bukur, D.B.; Rosynek, M.P. )

    1988-01-01

    The objective of this contract is to develop a consistent technical data base on the use of iron-based catalysts in Fischer-Tropsch (FT) synthesis reactions. This data base will be developed to allow the unambiguous comparison of the performance of these catalysts with each other and with state-of-the-art iron catalyst compositions. Particular attention will be devoted to generating reproducible kinetic and selectivity data and to developing reproducible improved catalyst compositions.

  20. Deactivation of slurry phase Fischer-Tropsch catalysts

    SciTech Connect

    Gormley, R.J.; Zarochak, M.F.; Deffenbaugh, P.W.; Rao, K.R.P.M.

    1996-12-31

    The influence of the liquid medium on Fischer-Tropsch (F-T) chemistry has received only minimal attention in the literature. The focus of this investigation was to determine the impact of the liquid starting medium on syngas (H{sub 2}+CO) conversion in a 1-liter CSTR. The results of the work indicate a greater deactivation rate for the F-T reaction in heavier starting media, average carbon number {ge}48, versus a medium with an average carbon number of 28.

  1. Separation of Fischer-Tropsch from Catalyst by Supercritical Extraction.

    SciTech Connect

    Joyce, P.C.; Thies, M.C.

    1997-10-31

    The objective of this research project is to evaluate the potential of supercritical fluid (SCF) extraction for the recovery and fractionation of the wax product from the slurry bubble column (SBC) reactor of the Fischer-Tropsch (F-T) process. The wax, comprised mostly of branched and linear alkanes with a broad molecular weight distribution up to C{sub 100}, will be extracted with a hydrocarbon solvent that has a critical temperature near the operating temperature of the SBC reactor, i.e., 200-300{degrees}C. Initial work is being performed using n-hexane as the solvent.

  2. Slurry phase Fischer-Tropsch synthesis: Cobalt plus a water-gas shift catalyst

    SciTech Connect

    Yates, I.C.; Satterfield, C.N.

    1988-01-01

    This report details experiments performed on three different copper-based catalysts: Cu/Cr[sub 2]O[sub 3], Cu/MnO/Cr[sub 2]O[sub 3] and Cu/ZnO/Al[sub 2]O[sub 3]. Of these three catalysts, the Cu/ZnO/Al[sub 2]O[sub 3] exhibits the greatest stability when slurried in octacosane. More than 1000 hours-on-stream indicate that the catalyst activity is not detrimentally affected by high pressure, high H[sub 2]/CO ratio, or the presence of alkenes. All of these are necessary stability characteristics for the water-gas shift catalyst, if it is to be used in combination with a cobalt Fischer-Tropsch catalyst. A review of documented reduction procedures for cobalt-based Fischer-Tropsch catalysts is presented.

  3. Novel Fischer-Tropsch slurry catalysts and process concepts for selective transportation fuel production: Quarterly technical progress report for the period 1 April-30 June 1986

    SciTech Connect

    Carroll, W.E.; Eliezer, K.F.; Mitchell, J.W.; Withers, H.P. Jr.

    1987-02-01

    In the seventh, and final quarter, work continued on the three major tasks: Task 2 - Development of Improved Supported Catalyst Compositions, Task 3 - Slurry Reactor Kinetic Studies, and Task 4 - Fuel Product Characterization. To examine the importance of surface area effects on the activity enhancement of the Co/Zr/silica catalyst, a Co/Zr/silica catalyst having the same surface area as the Co/Zr/alumina catalyst was tested in the fixed bed reactor. Silica provided an inherently more active catalyst than alumina but some of the enhancement that was initially observed was due to the increased surface area. The effect of increasing metal loadings on the performance of the Co/Zr/silica catalyst was examined with tests of 11% and 14.4$ Co catalysts in the fixed bed reactor. The 11% Co catalyst gave the highest syngas conversion (52%) at 220/sup 0/C of any catalyst tested at this temperature during this contract. Selectivity to liquid fuel product declined with increasing Co loading with an overall flattening of the hydrocarbon distribution. Slurry screening tests were performed on two catalysts. One was a cobalt on silica catalyst without any added promoter atoms such as Zr or Ti. The other screening test was a Zr promoted cobalt on silica catalyst with a high loading of Co. The extended slurry test which was begun in December 1985 was completed in June. During this quarter, a series of experiments was run to try to determine reaction kinetics. The spent catalyst from the extended slurry test of the Co/Zr/SiO/sub 2/ catalyst was found to contain 43.2% carbon and 2.4% hydrogen. This indicated a significant amount of coke formation. A second sample of liquid organic product was collected from the extended slurry test for testing as a diesel fuel. This sample met all the requirements for the highest quality diesel fuel except for viscosity and cloud point. 6 refs., 57 figs., 98 tabs.

  4. Effect of potassium promoter on cobalt nano-catalysts for fischer-tropsch reaction

    NASA Astrophysics Data System (ADS)

    Ali, Sardar; Mohd Zabidi, Noor Asmawati; Subbarao, Duvvuri

    2012-09-01

    In the present work effect of potassium on cobalt nano-catalysts for Fischer-Tropsch reaction has been presented. The catalysts were prepared using a wet impregnation method and promoted with potassium. Samples were characterized by nitrogen adsorption, H2-TPR, and TEM. The Fischer-Tropsch Synthesis (FTS) was carried out in a fixed-bed microreactor 220 δC, 1 atm, H2/CO = 2 and a velocity (SV) =12 L/g.h. for 5 h. Addition of potassium into Co/CNTs decreased the average size of cobalt nanoparticles and the catalyst reducibility. Potassium-promoted Co catalyst resulted in appreciable increase in the selectivity of C5+ hydrocarbons and suppressed methane formation. The 0.06%KCo/CNTs catalyst enhanced the C5+ hydrocarbons selectivity by a factor of 23.5% and reduced the methane selectivity by a factor of 39.6%

  5. Fischer Tropsch synthesis in supercritical fluids. Quarterly technical progress report, October 1, 1993--December 31, 1993

    SciTech Connect

    Akgerman, A.; Bukur, D.B.

    1993-12-31

    Objectives for the first quarter for Task A, Diffusion Coefficients of F-T Products in Supercritical Fluids, were to measure diffusion coefficients of 1-tetradecene in subcritical propane and the diffusion coefficients of 1-octene and 1-tetradecene in subcritical propane and the diffusion coefficients of 1-octene and 1-tetradecene in subcritical and supercritical ethane. We planned to use ethane as a solvent because its lower critical temperature enabled measurements without modification of the existing unit. Our objective was to investigate the behavior of the diffusion coefficients in crossing from subcritical to supercritical conditions. Objectives for Task B, Fischer Tropsch reaction related studies, were: (1) to install and test the temperature probe and the flammable gas detector: (2) to conduct Fischer-Tropsch experiments at baseline conditions and at a high pressure in order to test the newly constructed fixed bed reactor assembly. Accomplishments and problems, are presented.

  6. Catalyst and reactor development for a liquid phase Fischer-Tropsch process. Quarterly technical progress report, 1 April-30 June 1984

    SciTech Connect

    Carroll, W.E.; Cilen, N.; Motika, S.A.

    1985-03-01

    In the fifteenth quarter work continued for two major tasks: (1) Slurry Catalyst Development, and (2) Catalyst A Development. For task one, parametric gas phase screening tests were concluded on a ''modified'' conventional catalyst and an optimum preparation and activation procedure chosen for diesel fuel selectivity. A short term slurry test of this catalyst showed promising results. Further work in modifying the composition of this catalyst may be worthwhile. Two tests were conducted on Catalyst A this quarter: (1) A test to determine the effect of air calcination pretreatment. At the same process conditions, the bulk activity was nearly three times that of the uncalcined batch of this catalyst. The diesel fuel fraction, however, was considerably lower. (2) A retest of a modified version of this catalyst, A'. The results of this test indicte that: the selectivity of A' is highly dependent on the CO/H/sub 2/ ratio; temperature affects both the activity and product selectivity (a 15% increase in bulk activity and a shifting of products into the lower molecular weight region resulted from an increase in temperature from 240 to 260/sup 0/C); and reproducibility of lower temprature results are not possible after extended testing at a higher temperature level indication that the performance of the catalyst is dependent on its history of operating conditions. A number of gas phase activation procedures were tested on Catalyst A'. No appreciable difference in activity and selectivity was observed. A test of air calcination pretreatment before gas phase activation, however, resulted in an appreciable increase in bulk activity and increase in the yield of gasoline fuel.

  7. X-ray nanoscopy of cobalt Fischer-Tropsch catalysts at work.

    PubMed

    Cats, Korneel H; Gonzalez-Jimenez, Ines D; Liu, Yijin; Nelson, Johanna; van Campen, Douglas; Meirer, Florian; van der Eerden, Ad M J; de Groot, Frank M F; Andrews, Joy C; Weckhuysen, Bert M

    2013-05-21

    Transmission X-ray microscopy has been used to investigate individual Co/TiO2 Fischer-Tropsch (FT) catalyst particles in 2-D and 3-D with 30 nm spatial resolution. Tomographic elemental mapping showed that Co is heterogeneously concentrated in the centre of the catalyst particles. In addition, it was found that Co is mostly metallic during FT at 250 °C and 10 bar. No evidence for Co oxidation was found. PMID:23586073

  8. Fischer Tropsch synthesis in supercritical fluids. Quarterly technical progress report, January 1, 1994--March 31, 1994

    SciTech Connect

    Akgerman, A.; Bukur, D.B.

    1994-06-01

    We have successfully completed our first Fischer-Tropsch synthesis test with propane as the supercritical fluid. The catalyst activity and hydrocarbon product distribution under the SFT conditions were similar to those obtained during the normal Fischer-Tropsch synthesis, however, the use of supercritical fluid resulted in higher selectivity of the primary products. The use of a new trap with larger inside surface area, improved the collection of liquid products and thus enabling us to achieve better atomic and overall mass balance closures. This has also improved results from on-line GC analysis. However, further improvement are needed to achieve more stable and reproducible gas phase analysis, including the capability of the on-line analysis of the feed gas (mixture of hydrogen, carbon monoxide and propane).

  9. Catalyst and reactor development for a liquid phase Fischer-Tropsch process. Quarterly technical progress report, 1 October 1983-31 December 1983

    SciTech Connect

    Brian, B.W.; Carroll, W.E.; Cilen, N.; Pierantozzi, R.; Nordquist, A.F.

    1985-01-01

    Two major tasks continued in the thirteenth quarter: (1) Slurry Catalyst Development; and (2) Slurry Reactor Design Studies. In addition, work, as part of a three month contract modification, was begun to develop and improve the activity and center the selectivity for diesel fuel products of a proprietary catalyst A. This catalyst was found to produce yields in the diesel fuel region equal to or greater than the Schulz-Flory maximum with low rates of deactivation and good stability during previous extended periods of testing. A phase two extended slurry test of a proprietary catalyst B was completed this quarter. A considerable improvement in activity was observed, making this batch nearly four times as active as in the first phase of testing. The selectivity for total, gasoline and diesel, fuels was over 65 wt % in both phases of testing. The results of this test show the importance of metals loading and the need for further development work to optimize the activity and selectivity for diesel fuel of this catalyst. A short term (21 day) slurry test was conducted on another modified catalyst optimized by the gas phase screening program. Parametric gas phase screening tests were conducted on three additional catalysts. The optimum preparation and activation methods for diesel fuel selectivity will be chosen as these tests are completed. In the hydrodynamic studies, work in the 12 inch Cold-Flow Simulator was completed. A Box-Behnken experimental design was utilized to determine the statistical significance of the independent parameters studied (superficial gas velocity, solids weight fraction, solid size, etc.) on gas holdup, as well as, any synergistic effects. Correlations for gas holdup in the 12 inch and 5 inch columns were obtained. In each column, a strong linear dependence on superficial gas velocity was obtained. 6 references, 5 figures, 5 tables.

  10. Fischer-Tropsch catalysts for the production of hydrocarbon fuels with high selectivity.

    PubMed

    Zhang, Qinghong; Cheng, Kang; Kang, Jincan; Deng, Weiping; Wang, Ye

    2014-05-01

    Fischer-Tropsch synthesis is a key reaction in the utilization of non-petroleum carbon resources, such as methane (natural gas, shale gas, and biogas), coal, and biomass, for the sustainable production of clean liquid fuels from synthesis gas. Selectivity control is one of the biggest challenges in Fischer-Tropsch synthesis. This Minireview focuses on the development of new catalysts with controllable product selectivities. Recent attempts to increase the selectivity to C5+ hydrocarbons by preparing catalysts with well-defined active phases or with new supports or by optimizing the interaction between the promoter and the active phase are briefly highlighted. Advances in developing bifunctional catalysts capable of catalyzing both CO hydrogenation to heavier hydrocarbons and hydrocracking/isomerization of heavier hydrocarbons are critically reviewed. It is demonstrated that the control of the secondary hydrocracking reactions by using core-shell nanostructures or solid-acid materials, such as mesoporous zeolites and carbon nanotubes with acid functional groups, is an effective strategy to tune the product selectivity of Fischer-Tropsch synthesis. Very promising selectivities to gasoline- and diesel-range hydrocarbons have been attained over some bifunctional catalysts. PMID:24339240

  11. New ultrasonically prepared Co-based catalysts for Fischer-Tropsch synthesis.

    PubMed

    Bianchi, C L; Martini, F; Ragaini, V

    2001-04-01

    An extensive study of different preparation methods for Co/SiO2 catalysts is reported in this paper. In addition to the conventional impregnation, other more innovative methods are used including ultrasound. The prepared samples are fully characterized and tested in the CO hydrogenation (Fischer-Tropsch synthesis). The best catalytic performance, both as CO conversion and hydrocarbons selectivity, is shown by one of the sample prepared using ultrasound. PMID:11326608

  12. Novel Fischer-Tropsch slurry catalysts and process concepts for selective transportation fuel production. Quarterly technical progress report, 1 April-30 June 1985

    SciTech Connect

    Carroll, W.E.; Cilen, N.; Motika, S.A.; Withers, H.P. Jr.

    1986-07-01

    In the third quarter work continued on the two major tasks: Task 2 - Development of Improved Supported Catalyst Compositions; and Task 3 - Slurry Reactor Kinetic Studies. Within Task 2, work was accomplished in studying the effect of catalyst activation procedure on activity and selectivity of the basecase Co/sub 2/(CO)/sub 8/j/Zr(OPr)/sub 4//Al/sub 2/O/sub 3/ composition. Activation with pure H/sub 2/ gave a >100% increase in both bulk and specific activity in gas phase tests at 220/sup 0/C compared to the standard syngas activation. However, the activity enhancement was somewhat less at higher run temperatures. To establish a reference for the cobalt carbonyl-based catalysts, a catalyst was prepared and gas phase tested in which cobalt nitrate was used as the cobalt source and supported on zirconated alumina. Syngas and pure H/sub 2/ activation were also compared for this catalyst. A Co/sub 2/(CO)/sub 8//Zr(OPr)/sub 4//Al/sub 2/O/sub 3/ catalyst with increased cobalt loading was prepared to examine the effect of metal loading on catalyst performance. Initial analysis of these catalysts has been carried out using x-ray photoelectron spectroscopy (XPS) and H/sub 2/ chemisorption. Four catalysts were screened in the slurry phase reactors. These included the titanium promoted Co/sub 2/(CO)/sub 8/ on alumina catalyst, the Co/sub 2/(CO)/sub 8//Zr(OPr)/sub 4/ on alumina composition having a higher Co/Zr weight ratio of 1.15, and the potassium promoted mixed-metal composition of FeCo/sub 3/(CO)/sub 12/ on alumina. The fourth slurry screening test was done to examine the effect of pure H/sub 2/ activation on the performance of the basecase Co/sub 2/(CO)/sub 8//Zr(OPr)/sub 4/ on alumina catalyst. 63 figs., 131 tabs.

  13. Development of Precipitated Iron Fischer-Tropsch Catalysts

    SciTech Connect

    Burkur, D.B.; Ding, Y.; Chokkaram, S.

    1997-04-30

    Four (alumina or silica) supported catalysts were prepared by conventional impregnation of two commercial supports (silica - Davison grade 952; and alumina - Vista B). Nominal compositions (on mass basis) of synthesized catalysts are: (1) 100 Fe/5 Cu/6 K/139 SiO{sub 2} (2) 100 Fe/10 Cu/6 K/134 SiO{sub 2}, (3) 100 Fe/5 Cu/6 K/139 Al{sub 2}0{sub 3} and (4) 100 Fe/10 Cu/6 K/134 Al{sub 2}0{sub 3}. The corresponding weight % of iron (as metal) in the prepared catalysts is about 33.8%. Reduction behavior of the four supported catalysts was studied by both temperature programmed and isothermal reduction in hydrogen, and by isothermal reduction in CO at 280{degrees}C. Also, two precipitated promoted iron catalysts containing aluminum oxide as a binder, were reduced isothermally in the TGA unit with hydrogen at 240{degrees}C and 280{degrees}C. One of the two alumina containing catalysts (100 Fe/5 Cu/4.2 K/20 Al{sub 2}0{sub 3}) was tested in a slurry reactor (run SA-0097), and catalyst samples withdrawn from the reactor at various times on stream were characterized by XRD to determine bulk iron phases in the catalyst. Two slurry reactor tests were completed during this quarter. The first test (SA-0097) was conducted with alumina containing catalyst with nominal composition 100 Fe/5 Cu/4.2 K/20 Al{sub 2}0{sub 3}, which was synthesized previously in our laboratory (DOE Contract DE-AC22-85PC8001 1). The second test (SB-0627) was conducted with one of the silica supported catalysts which was prepared during this quarter: 100 Fe/5 Cu/6 K/139 SiO{sub 2} (Davison silica, grade 952). The performance of these two catalysts was inferior in comparison to our catalysts B (100 Fe/5 Cu/6 K/24 SiO{sub 2}) and C (100 Fe/3 Cu/4 K/16 SiO{sub 2}). Activity of these two catalysts was lower, catalyst deactivation rate was faster, and gaseous hydrocarbon selectivities were higher in comparison to the baseline catalysts B and C.

  14. Catalyst and reactor development for a liquid-phase Fischer-Tropsch process. Quarterly technical progress report, 1 October 1982-31 December 1982

    SciTech Connect

    Dyer, P.N.; Pierantozzi, R.; Brian, B.W.; Bauer, J.V.; Parsons, R.L.

    1983-03-01

    Two major tasks were continued: (1) Slurry Catalyst Development, and (2) Slurry Reactor Design Studies. The first extended slurry test was begun, using a proprietary catalyst. High selectivities and large deviations from the Schulz-Flory distribution were observed. A bulk activity 2.5 times greater than the baseline Fe/sub 2/O/sub 3/ was determined, with little deactivation over 450 h. Consistently low CH/sub 4/ yields of 3 to 5 wt %, and high C/sub 9/-C/sub 25/ fractions of 45 to 50 wt %, were produced at 240/sup 0/C, 300 psig and 1:1 CO/H/sub 2/. This test is being continued with higher CO/H/sub 2/ ratios and operating temperatures. Parametric gas phase screening studies were concluded for two further modified conventional catalysts and the optimum preparations in terms of activity and diesel range selectivity were chosen for subsequent slurry phase testing. Gas holdup and solid concentration profiles were measured for water/silica slurries in the 5'' column, and for paraffin/silica slurries in the 12'' column, both with and without heat transfer internals. In both columns, gas holdup was found to be close to the Akita and Yoshida correlation. Very non-uniform solid concentration profiles were observed in the 2 column for the 90 to 115 ..mu..m size silica, with settling of the slurry on the distributor plate. Smaller size particles were more uniformly distributed. Heat transfer coefficients were determined in the 12'' column for paraffin/silica slurries, using seven vertical, tubular heat transfer elements. The values were in good agrement with Deckwer's correlation for the large and medium size particles, but were lower for the 0.5 to 5 ..mu..m size range. The bubble size diameter probe was successfully calibrated using a strobe technique, and data acquisition will begin next quarter.

  15. Fischer-Tropsch slurry phase process variations. Quarterly report, April 1-June 30, 1986

    SciTech Connect

    Satterfield, C.N.; Hanlon, R.; Matsumoto, D.K.

    1986-01-01

    In studies at 232/sup 0/C and 248/sup 0/C and 0.92 MPa, during the first 20 hours on stream, both Fischer-Tropsch synthesis activity and CO consumption increased to quasi-steady-state values. The bulk catalyst, initially ..cap alpha..-Fe, was converted to a mixture of ..cap alpha..-Fe and iron carbides, as determined by Moessbauer spectroscopy. During the first few hours, methane selectivity decreased markedly while the olefin/paraffin ratio increased. No change was observed in the C/sub 2/-C/sub 8/ product distribution with time on stream. When an industrial iron-based Fischer-Tropsch catalyst is first put on stream some 20 to 40 hours may elapse before its activity and selectivity approach steady-state conditions and during this time the phases present in the catalyst usually change markedly. The present study used a fused triply-promoted magnetite catalyst, sold for use in ammonia synthesis, which is very similar to one of the kinds of iron catalyst used industrially at SASOL in South Africa. It was completely reduced initially. Reaction was carried out in semi-continuous fashion in a well-stirred 1-litter autoclave. We were particularly concerned with studying the activity and selectivity of this catalyst as it approached steady-state behavior and determining if this correlated with the phases present in the catalyst as determined by Moessbauer spectroscopy. 20 refs., 9 figs., 1 tab.

  16. Fischer-Tropsch process

    DOEpatents

    Dyer, Paul N.; Pierantozzi, Ronald; Withers, Howard P.

    1987-01-01

    A Fischer-Tropsch process utilizing a product selective and stable catalyst by which synthesis gas, particularly carbon-monoxide rich synthesis gas is selectively converted to higher hydrocarbons of relatively narrow carbon number range is disclosed. In general, the selective and notably stable catalyst, consist of an inert carrier first treated with a Group IV B metal compound (such as zirconium or titanium), preferably an alkoxide compound, and subsequently treated with an organic compound of a Fischer-Tropsch metal catalyst, such as cobalt, iron or ruthenium carbonyl. Reactions with air and water and calcination are specifically avoided in the catalyst preparation procedure.

  17. Reaction engineering of slurry phase Fischer-Tropsch synthesis with porous cobalt catalysts

    SciTech Connect

    Han, Y.H.; Li, F.; Fujimoto, Kaoru

    1997-12-31

    Fischer-Tropsch synthesis was conducted in the slurry phase using a stirred reactor and supported cobalt catalysts. Under well stirred conditions, neither the mass transfer between the gas-solid interface nor the liquid-solid interface was found to be the rate limiting step in the reaction sequence. The catalytic activity and product selectivity were markedly affected by the particle size for small pore (20 angstroms) catalyst while those of a large pore catalyst were not affected by the particle where the partial diameter is larger than 0.1 mm. The phenomena were well simulated by theoretical calculations.

  18. Development and process evaluation of improved Fischer-Tropsch slurry catalysts. Final report

    SciTech Connect

    Bukur, D.B.; Mukesh, D.; Patel, S.A.; Zimmerman, W.H.; Rosynek, M.P.; Kellogg, L.J.

    1990-04-01

    This report describes results of a study aimed at developing and evaluating improved catalysts for a slurry Fischer-Tropsch (FT) process for converting synthesis gas to high quality transportation fuels (gasoline and distillate). The improvements in catalyst performance were sought by studying effects of pretreatment conditions, promoters and binders/supports. A total of 20 different, iron based, catalysts were evaluated in 58 fixed bed reactor tests and 10 slurry reactor tests. The major accomplishments and conclusions are summarized below. The pretreatment conditions (temperature, duration and the nature of reducing gas) have significant effect on catalyst performance (activity, selectivity and stability) during Fischer-Tropsch synthesis. One of precipitated unsupported catalysts had hydrocarbon selectivity similar to Mobil`s I-B catalyst in high wax mode operation, and had not experienced any loss in activity during 460 hours of testing under variable process conditions in a slurry reactor. The effect of promoters (copper and potassium) on catalyst performance during FT synthesis has been studied in a systematic way. It was found that potassium promotion increases activities of the FT and water-gas-shift (WGS) reactions, the average molecular weight of hydrocarbon products, and suppresses the olefin hydrogenation and isomerization reactions. The addition of binders/supports (silica or alumina) to precipitated Fe/Cu/K catalysts, decreased their activity but improved their stability and hydrocarbon selectivity. The performance of catalysts of this type was very promising and additional studies are recommended to evaluate their potential for use in commercial slurry reactors.

  19. Development and process evaluation of improved Fischer-Tropsch slurry catalysts: Quarterly technical progress report for the period 1 April to 30 June 1987

    SciTech Connect

    Withers, H.P.; Bukur, D.B.; Rosynek, M.P.

    1987-08-25

    Three runs were made with a commercial fused iron catalyst with objectives to study the effects of catalyst reduction procedure, particle size and process conditions on fixed bed reactor performance (activity and product selectivity). The catalyst activity increases as the space velocity of H/sub 2/ during the reduction increases or as the catalyst particle size decreases. An uncalcined precipitated iron catalyst (100 Fe/1 Cu/0.2 K on weight basis) was evaluated in a fixed bed reactor. Initially, it showed an activity more than twice of the fused iron catalyst, but it deactivated after about 30 hours on stream. The work on catalyst synthesis and characterization of the precipitated iron catalysts has continued. 25 precipitated iron catalysts (Fe/Cu, Fe/K and Fe/Cu/K) have been prepared. Temperature programmed reduction has revealed that the iron reduction is facilitated in the presence of copper. Also, unpromoted iron and potassium promoted iron (containing 1 part K per 100 parts Fe) were examined using Fourier Transform Infrared Spectroscopy. 9 refs., 19 figs., 8 tabs.

  20. Slurry phase Fischer-Tropsch synthesis: Cobalt plus a water-gas shift catalyst

    SciTech Connect

    Chanenchuk, C.A.; Yates, I.C.; Satterfield, C.N.

    1990-01-01

    A Co/MgO/SiO[sub 2] Fischer-Tropsch catalyst was operated simultaneously with a Cu/ZnO/Al[sub 2]O[sub 3] water-gas-shift catalyst in a slurry reactor for over 400 hours. The process conditions were held constant at a temperature of 240[degrees]C, a pressure of 0.79 MPa, and a 1.1 H[sub 2]/CO feed of 0.065 Nl/min-g.cat. The Fischer-Tropsch activity remained constant at the level predicted by the operation of the Co/MgO/SiO[sub 2] catalyst alone. The water-gas-shift reaction was near equilibrium. The hydrocarbon product distribution of the combined catalyst system was stable and matched that of the CO/MgO/SiO[sub 2] operating alone under similar conditions. The combined catalyst system exhibited a high selectivity to n-alkanes. Neither catalysts's operation appeared to have a detrimental effect on that of the other, showing promise for future option.

  1. Development and process evaluation of improved Fischer-Tropsch slurry catalysts: Quarterly technical progress report for the period 17 October 1986 to 31 January 1987

    SciTech Connect

    Withers, H.P.; Bukur, D.B.; Rosynek, M.P.

    1987-03-23

    A literature search of precipitated iron/copper/potassium catalyst has been completed. A catalyst precipitation unit has been assembled and tested. A pure precipitated iron catalyst has been synthesized and its BET surface area and temperature-programmed reduction (TPR) behavior have been determined. All equipment supplied by APCI has been made operational. The design of two new reactor systems (slurry and fixed bed) has been completed, and some of the equipment and parts necessary for their construction have arrived. Progress has been made in the areas of chromatograph calibrations and data reduction software. 24 refs., 6 figs., 8 tabs.

  2. Catalyst and reactor development for a liquid phase Fischer-Tropsch process. Quarterly technical progress report, 1 July 1983-30 September 1983

    SciTech Connect

    Brian, B.W.; Carroll, W.E.; Cilen, N.; Pierantozzi, R.; Nordquist, A.F.

    1984-11-01

    Two major tasks of the contract continued: (1) slurry catalyst development, and (2) slurry reactor design studies. The second extended slurry test, using a proprietary catalyst was completed. The results were not consistent with a previous short term test of this catalyst where high activity and yields in the diesel fuel region equal to or greater than the Schulz-Flory maximum were observed. The increased methane production and lower bulk activity over the previous test may have been the result of a variation in the surface active species of this catalyst. A short term (21 day) slurry test was carried out on another modified conventional catalyst. Parametric gas phase screening results were concluded for four additional catalysts, and the optimum preparation and activation methods for diesel fuel selectivity were chosen. In the hydrodynamic studies, work in the 12 inch Cold Flow Simulator continued. The following observations and/or conclusions were obtained: superficial gas velocity is the major factor for determining gas holdup; the major determining factor of the solids concentration profile in a slurry bed is particle size; heat transfer coefficients for the two-phase isoparaffin/N/sub 2/ were 64% of that predicted by Deckwer's correlation and for the three-phase Fe/sub 2/O/sub 3//isoparaffin, the results were better at 71%; bubble diameter measurements were obtained using a double hot film probe; the Air Products gas holdup correlation was incorporated into Deckwer's model of the three phase bubble column. A simulation utilizing kinetic data from an Air Products diesel fuel selective catalyst, under Rheinpreussen conditions, resulted in doubling the space time yield of the Rheinpreussen base case catalyst. 9 references, 12 figures, 8 tables.

  3. Catalyst and reactor development for a liquid phase Fischer-Tropsch process. Quarterly technical progress report, 1 April-30 June 1983

    SciTech Connect

    Brian, B W; Carroll, W E; Cilen, N; Pierantozzi, R; Nordquist, A F

    1984-10-01

    Two major tasks of the contract continued: (1) Slurry Catalyst Development, and (2) Slurry Reactor Design Studies. A third phase of the extended slurry test of the proprietary catalyst was conducted using a new catalyst batch to confirm that the change in selectivity and loss of activity, observed in the second phase, was due to air exposure of the catalyst. The results were in line with the high diesel fuel production as before the suspected oxidation. Excess CO exposure during this last phase of testing resulted in a reduction in catalyst activity and a shift in selectivity to heavier hydrocarbons with a Schulz-Flory maximum centered around C/sub 30/. The variations in selectivity and activity upon oxidation through air exposure, or surface carbon deposition through excess CO exposure, have confirmed the importance of understanding the mechanism for product selectivity. Further development with the aid of surface analysis techniques is required to control and center the selectivity for the diesel fuel range. Short term slurry tests were carried out on three catalysts, the preparation and activation procedures of which were optimized by the gas phase screening program. In the hydrodynamic studies, correlations were derived for the 5'' column data. In the 12'' column, fitted with 7 vertical heat transfer tubes, hydrodynamic parameters were determined for slurries of 45 to 90 ..mu..m Fe/sub 2/O/sub 3/ in paraffin and water. A double, conical, hot film probe to measure bubble diameter was successfully operated in a three phase slurry. Using Deckwer's model of the three phase bubble column, and kinetic data derived from the lab CSTR tests, the performance of Air Products' selective catalysts in a 1.5 x 8 m column (i.e., the size of Rheinpruessen) was simulated under both quiescent and churn turbulent conditions. 7 references, 8 figures, 6 tables.

  4. Catalyst and reactor development for a liquid-phase Fischer-Tropsch process. Quarterly technical progress report, 1 April 1982-30 June 1982

    SciTech Connect

    Dyer, P.N.; Pierantozzi, R.; Brian, B.W.; Bauer, J.V.

    1982-08-01

    Two major current tasks are: Slurry Catalyst Development, and Slurry Reactor Design Studies. Seven supported conventional catalysts, prepared with different metal precursors, concentrations, calcination procedures and supports, were tested in the gas phase to determine the effect of these parameters on activity and selectivity. A second slurry test of the baseline catalyst, sintered Fe/sub 2/O/sub 3/, utilized CO rich syngas to determine reactor mass transfer limitations. The product from 1.4:1 CO/H/sub 2/ approximated a straight line Schulz-Flory distribution, but higher CO/H/sub 2/ ratios gave increased high molecular weight material. Methane yields were low and high water gas shift activity gave a close match between syngas feed and usage ratios. At T > 250/sup 0/C some mass transfer effects were observed, and are being incorporated into a reactor model. Six additional slurry tests used supported molecular cluster catalysts. Initially in this series, slurry phase activities were low. A slurry test of one supported cluster showed marked deviations from the standard Schulz-Flory distribution in the C/sub 10/-C/sub 29/ region, but at very low conversion. Subsequent supported cluster catalyst tests led to a method of obtaining high slurry phase activities equal to the gas phase. A slurry test of another cluster catalyst utilizing this method gave high activity, but did not reproduce the product selectivity for C/sub 10/-C/sub 18/ observed in its previous gas phase test. At higher pressure, 750 psig, and 280/sup 0/C, however, methane yields decreased, becoming independent of the CO/H/sub 2/ ratio, and the Schulz-Flory product distribution became nonlinear with a definite cutoff at approx. C/sub 28/. Two supported cluster catalysts were prepared and seven were screened in the gas phase.

  5. Synthesis and catalytic properties of eggshell cobalt catalysts for the Fischer-Tropsch synthesis

    SciTech Connect

    Iglesia, E.; Soled, S.L.; Baumgartner, J.E.

    1995-04-15

    CO diffusional restrictions decrease the rate and C{sup +}{sub 5} selectivity in large (1-3 mm) catalyst pellets required for Fischer-Tropsch synthesis in packed bed reactors. Eggshell catalysts, in which the active Co component is preferentially located near the outer pellet surface, decrease these transport restrictions and increase Fischer-Tropsch synthesis rates and C{sup +}{sub 5} selectivity. Maximum C{sup +}{sub 5} selectivities occur on catalysts with intermediate shell thickness, because these catalysts avoid intrapellet CO concentration gradients but still restrict the diffusive removal of reactive olefin products, which can readsorb and continue to grow to higher molecular weight hydrocarbons. Eggshell catalysts were prepared by a novel impregnation technique using molten cobalt nitrate. The eggshell thickness is controlled by the melt viscosity and by the contact time between the melt and the support pellet. These impregnation procedures and the slow reduction of the impregnated nitrate salts lead to relatively high cobalt dispersions (0.05-0.07) even at the high Co concentrations (40-50 wt%) present within the shell region. 51 refs., 8 figs., 4 tabs.

  6. Cobalt cluster effects in zirconium promoted Co/SiO{sub 2} Fischer-Tropsch catalysts

    SciTech Connect

    Feller, A.; Claeys, M.; Steen, E. van

    1999-07-01

    The effect of zirconium addition to the catalyst formulation of Co/SiO{sub 2} Fischer-Tropsch catalysts was investigated. With increasing zirconium content the strong interaction between silica and cobalt is reduced and a somewhat weaker cobalt-zirconium interaction is observed. Therefore the degree of reduction of catalysts, which were reduced at 400 C for 16 h, increases strongly. The cobalt crystallite size increases with increasing zirconium content, leading to smaller cobalt metal surface areas for the freshly reduced catalyst. Cobalt particles can be found in clusters on the silica support. The size of cobalt clusters decreases and thus the number of cobalt particles within a cluster decreases with increasing zirconium content. At steady-state conditions the CO-conversion of the promoted catalyst in the Fischer-Tropsch synthesis increases with increasing zirconium content. The C{sub 5+}-selectivity and the secondary hydrogenation activity pass a maximum with increasing zirconium content. The observed changes in activity and selectivity are explained in terms of an increase in the amount of metallic cobalt available under reaction conditions, leading to an increased activity, and a decrease in the cobalt cluster size, which diminishes the probability for secondary reactions. Furthermore, it was concluded that secondary double bond isomerization can be catalyzed to some extent by zirconia.

  7. Catalyst and reactor development for a liquid-phase Fischer-Tropsch process. Quarterly technical progress report, 1 October 1981-31 December 1981

    SciTech Connect

    Dyer, P.N.; Pierantozzi, R.; Brian, B.W.; Bauer, J.V.

    1982-01-01

    This program contains four major tasks: (1) Project Work Plan, (2) Slurry Catalyst Development, (3) Slurry Reactor Design Studies, and (4) Pilot Facility Design. In Task 2, five modified conventional catalysts were prepared, and six gas phase screening tests were carried out. One of these catalysts gave an excellent diesel fuel type product distribution, with a low CH/sub 4/ yield and good stability. Two slurry tests were run. The first used a 19 wt % slurry of ammonia synthesare catalyst as a baseline F-T case, and incorporated the slurry reactor mass transfer tests by varying stirring rates and space velocities as a function of temperature. Product distributions were straight line Schulz-Flory, as expected with this type of catalyst. The data are currently being analyzed to separate mass transfer and chemical rate effects. The second utilized a slurry of a coprecipitated catalyst, activated in the slurry phase. The pressure and temperature required for activation and reaction were found to be higher than for the gas phase screening tests, and deviations from the standard hydrocarbon product distribution were small. The usage and feed ratios were equal for 1:1 syngas. Seven supported cluster catalysts were synthesized and eight were screened in the gas phase. One of these produced a high selectivity to 1-butene and n-pentane. In Task 3, measurements of gas hold-up and solids dispersion in the 5'' column were completed for the 45 to 53 ..mu..m and 90 to 106 ..mu..m iron oxide/isoparaffin systems. Contrary to the silica slurry results, an increase in gas hold-up was observed with a positive slurry velocity. No dependence of gas hold-up on distributor type was observed, however. With the 43 to 53 ..mu..m slurry, the solids concentration profiles were uniform under all conditions studied, but with the 90 to 106 ..mu..m slurry, a decrease in solids concentration with column height was observed at zero slurry velocity.

  8. Nano-sized cobalt based Fischer-Tropsch catalysts for gas-to-liquid process applications.

    PubMed

    Kang, Jung Shik; Awate, S V; Lee, Yun Ju; Kim, So Jung; Park, Moon Ju; Lee, Sang Deuk; Hong, Suk-In; Moon, Dong Ju

    2010-05-01

    Nano-sized cobalt supported catalysts were prepared for Fischer-Tropsch synthesis in gas-to-liquid (GTL) process. The dependence of crystallite size and reducibility of Co3O4 on the supports were investigated with FTS activity. XRD peaks revealed nano crystallites (< 5.47 nm) of Co3O4 crystallites. TEM showed round shaped particles with size less than 5 nm. Support with higher acidity decreased crystallite size of Co3O4. XRD data of used catalysts showed Co3O4 crystallites smaller than 3.5 nm which do not reduce easily to Co(0) state. The crystallite size of Co3O4 plays a role in its reduction to Co(0). TPR results showed that the reduction temperature shifts to higher temperature due to metal-support interaction. The variation in the activity of the catalysts depends on the support which in turn affects the crystallite size, dispersion, reducibility and activity of Co species in Fischer-Tropsch Synthesis (FTS). In this study, Co/Al2O3 showed higher CO conversion than the other catalysts. However, the C5+ production was in order Co/SiO2 (78.1%) > Co/Al2O3 (70.0%) > Co/R_TiO2 (61%) > Co/A_TiO2 (57.5%). PMID:20359031

  9. Slurry phase Fischer-Tropsch synthesis: Cobalt plus a water-gas shift catalyst. [Quarterly] report, April 1, 1990--June 30, 1990

    SciTech Connect

    Yates, I.C.; Satterfield, C.N.

    1990-12-31

    Experiments on cobalt-catalyzed reactions of light 1-alkenes added to synthesis gas were performed. Data have been collected at 220C, 0.45 to 1.48 MPa and a synthesis gas flow rate between 0.015 and 0.030 Nl/(gcat{center_dot}min) with H{sub 2}/CO of 1.45 to 2.25. Ethylene, propene, and butene were added to synthesis gas feed from 0.5 to 1.2 mole% of total feed. For each material balance in which 1-alkenes were added, a material balance was performed at similar process conditions without 1-alkenes added, as ``base case``. Material balances without added 1-alkenes were also repeated to verify of catalyst selectivity stability. 49 material balances were performed during a single run lasting over 2,500 hours-on-stream. The hydrocarbon data have been completely analyzed; data correlations are still being made. Since C{sub 3}/C{sub 1} ratios by ethene addition, C{sub 4}/C{sub 1} ratios by propene addition, and C{sub 5}/C{sub 1} ratios by 1-butene addition, it appears that 1-alkenes may incorporate into growing chains on the surface of the catalyst. Further evidence for incorporation can be seen by comparing selectivity to n-alcohol one carbon number higher than added 1-alkene. Yield of this n-alcohol increases when alkenes are present. Sensitivity of hydrocarbon distribution to process variables seems to be greater on Co than on Fe catalysts.

  10. Catalyst and reactor development for a liquid phase Fischer-Tropsch process

    SciTech Connect

    Not Available

    1989-01-01

    The preparation, characterization, and performance of a range of metal catalysts for use in slurry phase Fischer-Tropsch technology was investigated with the objective of developing new compositions with improved selectivity for gasoline and diesel fuel range hydrocarbons. A series of conventional catalysts was identified for testing for both gas and slurry phases. A gas phase screening protocol was set up to allow reasonably rapid determination of each catalyst's synthesis gas conversion characteristic over a range of operating conditions. The catalysts selected represented a range of catalytic metals known to promote conversion of synthesis gas to hydrocarbon liquids. Both precipitates and supported variations of these metals were studied. Catalysts studied include: ruthenium-based catalysts with osmium, and cobalt carbonyl supported on zirconia promoted. 23 refs., 2 figs., 10 tabs.

  11. Nitrided iron catalysts for the Fischer-Tropsch synthesis in the eighties

    SciTech Connect

    Anderson, R.B.

    1980-01-01

    A survey covers the preparation and structure of nitrided iron catalysts and their activity, selectivity, and stability for the reaction of synthesis gas in comparison with iron catalysts pretreated by various other methods, as measured in laboratory reactors; a comparison of product distributions obtained in fluidized-bed, slurry, and oil-circulation fixed bed pilot plants with nitrided catalysts and by the Kellogg entrained catalyst process SASOL, which uses a reduced iron catalyst; and possible methods for refining the Fischer-Tropsch products from nitrided iron catalysts for producing gasoline, including bauxite treatment, the Mobil process for converting oxygenates to high-octane gasoline and C/sub 3/-C/sub 4/ olefins, and an alkylation-polymerization process for converting the C/sub 3/-C/sub 4/ fraction to high-octane blending stocks.

  12. Iron and cobalt Fischer-Tropsch catalysts prepared by the solvated metal-atom technique

    SciTech Connect

    Meier, P.F.; Pennella, F.; Klabunde, K.J.; Imizu, Y.

    1986-10-01

    It is reasonable that at low metal loadings a more active catalyst would result from deposition on a support of a metal in the reduced, metallic state. Deposition of less than 5 wt% cobalt on alumina in the form of cobalt carbonyl produced catalysts of good activity. The Solvated Metal Atom Deposition Technique (SMAD) provides a method of catalyst preparation for which the deposition of metallic catalysts on a support has been demonstrated. This note reports a comparative study of the Fischer-Tropsch synthesis activity of iron and cobalt catalysts prepared by this technique and supported on silica with less than 5 wt% of the metal, and of analogous catalysts prepared by conventional impregnation techniques. 16 references.

  13. Nanoscale attrition during activation of precipitated iron Fischer-Tropsch catalysts: Implications for catalyst design

    SciTech Connect

    Datye, A.K.; Shroff, M.D.; Jin, Y.; Brooks, R.P.; Wilder, J.A.

    1996-12-31

    The Fischer-Tropsch Synthesis (FTS) for the production of liquid hydrocarbons from coal-based synthesis gas has been the subject of renewed interest for conversion of coal to liquid fuels. The use of synthesis gas from modem energy-efficient gasifiers requires catalysts that can operate under low H{sub 2}/CO ratios, typically 0.7-0.9. Since the FTS stoichiometry requires a H{sub 2}/CO ratio of 2.0, catalysts that operate at lower ratios must catalyze the water gas shift reaction to make up the deficit in H{sub 2}. The use of iron-based catalysts for the process is attractive in view of their low cost, ready availability and high water-gas shift reactivity. Furthermore, iron catalysts at elevated pressures (10-15 atmospheres) produce the desired range of liquid hydrocarbons. AU these features make the use of Fe as an F-T catalyst extremely desirable. Since the reaction is highly exothermic, the preferred reactor type for industrial operation is the slurry bubble column reactor. The catalyst for this reactor is precipitated iron oxide which is spray dried to yield particles with diameter of 30-70 {mu}m. One major limitation of these catalysts is that they tend to undergo attrition during use, leading to problems in catalyst separation and recovery of liquid products from the reactor.

  14. Low nitrogen iron-containing Fischer-Tropsch catalyst for conversion of synthesis gas and process for preparing the catalyst

    SciTech Connect

    Bell, W.K.; Haag, W.O.; Kirker, G.W.; Klocke, D.J.

    1986-10-14

    A process is described for preparing an iron-containing Fischer-Tropsch catalyst by continuously precipitating an aqueous solution containing iron nitrate with aqueous ammonia, to form a precipitate-containing product which is thereafter dried. In the improvement described here a catalyst containing less than 500 ppm nitrogen is produced which comprises maintaining a pH of about 6.5 to 6.9 and a temperature of about 70/sup 0/ to 100/sup 0/ C. during precipitation.

  15. Attrition resistant Fischer-Tropsch catalyst and support

    DOEpatents

    Singleton, Alan H.; Oukaci, Rachid; Goodwin, James G.

    2004-05-25

    A catalyst support having improved attrition resistance and a catalyst produced therefrom. The catalyst support is produced by a method comprising the step of treating calcined .gamma.-alumina having no catalytic material added thereto with an acidic aqueous solution having an acidity level effective for increasing the attrition resistance of the calcined .gamma.-alumina.

  16. Mechanism of promotion of iron Fischer-Tropsch catalysts: Final report

    SciTech Connect

    Tau, L.M.; Dabbagh, H.; Chawla, B.; Davis, B.H.

    1987-12-31

    The kinetic isotope method (KIM) has been utilized in a study designed to determine the way in which promoters for iron catalysts impact the variety of primary and secondary reactions in the Fischer-Tropsch synthesis (FTS). The KIM involves the addition of known or suspected intermediates to the synthesis gas feed. In order to follow the conversion of the added compound, and the products formed as a result of the addition, the added compound is labeled with a radioactive isotope of carbon. An analysis of the Fischer-Tropsch synthesis products readily permits one to identify those compounds that are derived from the added compound. Using this technique, results were obtained with unpromoted iron, iron promoted by Al/sub 2/O/sub 3/, ThO/sub 2/, ZrO/sub 2/, and SiO/sub 2/, and alkali promoted iron catalysts. A combination of gas chromatographic, dry column chromatographic and liquid chromatographic techniques allowed us to determine the /sup 14/C present in compounds over the C/sub 1/--C/sub 22/ range in the alkane and alkene fractions. A continuous stirred tank reactor (CSTR) was used for most of the experimental studies. 108 refs., 100 figs., 6 tabs.

  17. Iron Aerogel and Xerogel Catalysts for Fischer-Tropsch Synthesis of Diesel Fuel

    SciTech Connect

    Bali, S.; Huggins, F; Huffman, G; Ernst, R; Pugmire, R; Eyring, E

    2009-01-01

    Iron aerogels, potassium-doped iron aerogels, and potassium-doped iron xerogels have been synthesized and characterized and their catalytic activity in the Fischer-Tropsch (F-T) reaction has been studied. Iron aerogels and xerogels were synthesized by polycondensation of an ethanolic solution of iron(III) chloride hexahydrate with propylene oxide which acts as a proton scavenger for the initiation of hydrolysis and polycondensation. Potassium was incorporated in the iron aerogel and iron xerogel by adding aqueous K{sub 2}CO{sub 3} to the ethanolic solutions of the Fe(III) precursor prior to addition of propylene oxide. Fischer-Tropsch activities of the catalysts were tested in a fixed bed reactor at a pressure of 100 psi with a H{sub 2}:CO ratio of 2:1. Iron aerogels were found to be active for F-T synthesis, and their F-T activities increased on addition of a K containing promoter. Moessbauer spectroscopic data are consistent with an open, nonrigid iron(III) aerogel structure progressing to an iron carbide/metallic iron catalyst via agglomeration as the F-T synthesis proceeds in the course of a 35 h fixed bed reaction test.

  18. Development of attrition resistant iron-based Fischer-Tropsch catalysts

    SciTech Connect

    2000-09-20

    The Fischer-Tropsch (F-T) reaction provides a way of converting coal-derived synthesis gas (CO+H{sub 2}) to liquid fuels. Since the reaction is highly exothermic, one of the major problems in control of the reaction is heat removal. Recent work has shown that the use of slurry bubble column reactors (SBCRs) can largely solve this problem. The use of iron-based catalysts is attractive not only due to their low cost and ready availability, but also due to their high water-gas shift activity which makes it possible to use these catalysts with low H{sub 2}/CO ratios. However, a serious problem with use of Fe catalysts in a SBCR is their tendency to undergo attrition. This can cause fouling/plugging of downstream filters and equipment, makes the separation of catalyst from the oil/wax product very difficult if not impossible, and results a steady loss of catalyst from the reactor. The objective of this research is to develop robust iron-based Fischer-Tropsch catalysts that have suitable activity, selectivity and stability to be used in the slurry bubble column reactor. Specifically we aim to develop to: (1) improve the performance and preparation procedure of the high activity, high attrition resistant, high alpha iron-based catalysts synthesized at Hampton University (2) seek improvements in the catalyst performance through variations in process conditions, pretreatment procedures and/or modifications in catalyst preparation steps and (3) investigate the performance in a slurry reactor. The effort during the reporting period has been devoted to effects of pretreating procedures, using H{sub 2}, CO and syngas (H{sub 2}/CO = 0.67) as reductants, on the performance (activity, selectivity and stability with time) of a precipitated iron catalyst (100Fe/5Cu/4.2K/10SiO{sub 2} on a mass basis ) during F-T synthesis were studied in a fixed-bed reactor.

  19. Attrition Resistant Fischer-Tropsch Catalysts Based on FCC Supports

    SciTech Connect

    Adeyiga, Adeyinka

    2010-02-05

    Commercial spent fluid catalytic cracking (FCC) catalysts provided by Engelhard and Albemarle were used as supports for Fe-based catalysts with the goal of improving the attrition resistance of typical F-T catalysts. Catalysts with the Ruhrchemie composition (100 Fe/5 Cu/4.2 K/25 spent FCC on mass basis) were prepared by wet impregnation. XRD and XANES analysis showed the presence of Fe{sub 2}O{sub 3} in calcined catalysts. FeC{sub x} and Fe{sub 3}O{sub 4} were present in the activated catalysts. The metal composition of the catalysts was analyzed by ICP-MS. F-T activity of the catalysts activated in situ in CO at the same conditions as used prior to the attrition tests was measured using a fixed bed reactor at T = 573 K, P = 1.38 MPa and H{sub 2}:CO ratio of 0.67. Cu and K promoted Fe supported over Engelhard provided spent FCC catalyst shows relatively good attrition resistance (8.2 wt% fines lost), high CO conversion (81%) and C{sub 5}+ hydrocarbons selectivity (18.3%).

  20. Development of improved iron Fischer-Tropsch catalysts

    SciTech Connect

    Bukur, D.B.

    1991-10-28

    The objective of proposed research is development of catalysts with enhanced slurry phase activity and better selectivity to fuel range products, through a more detailed understanding and systematic studies of the effects of pretreatment procedures and promoters/binders (silica) on catalyst performance.

  1. Development of improved iron Fischer-Tropsch catalysts

    SciTech Connect

    Bukur, D.B.

    1990-10-29

    The objective of proposed research is development of catalysts with enhanced slurry phase activity and better selectivity to fuel range products, through a more detailed understanding and systematic studies of the effects of pretreatment procedures and promoters/binders (silica) on catalyst performance.

  2. Development of improved iron Fischer-Tropsch catalysts

    SciTech Connect

    Bukur, D.B.

    1991-07-19

    The objective of proposed research is development of catalysts with enhanced slurry phase activity and better selectivity to fuel range products, through a more detailed understanding and systematic studies of the effects of pretreatment procedures and promoters/binders (silica) on catalyst performance.

  3. Development of improved iron Fischer-Tropsch catalysts

    SciTech Connect

    Bukur, D.B.

    1991-04-24

    The objective of proposed research is development of catalysts with enhanced slurry phase activity and better selectivity to fuel range products, through a more detailed understanding and systematic studies of the effects of pretreatment procedures and promoters/binders (silica) on catalyst performance.

  4. Development of improved iron Fischer-Tropsch catalysts

    SciTech Connect

    Bukur, D.B.

    1991-01-25

    The objective of proposed research is development of catalysts with enhanced slurry phase activity and better selectivity to fuel range products, through a more detailed understanding and systematic studies of the effects of pretreatment procedures and promoters/binders (silica) on catalyst performance.

  5. Development of improved iron Fischer-Tropsch catalysts

    SciTech Connect

    Bukur, D.B.

    1990-06-17

    The objective of proposed research is development of catalysts with enhanced slurry phase activity and better selectivity to fuel range products, through a more detailed understanding and systematic studies of the effects of pretreatment procedures and promoters/binders (silica) on catalyst performance.

  6. Development of improved iron Fischer-Tropsch catalysts

    SciTech Connect

    Bukur, D.B.; Patel, S.A.; Dalai, A.K.; Jayanthi, G.; Ledakowicz, S.

    1990-04-30

    The objective of proposed research is development of catalysts with enhanced slurry phase activity and better selectivity to fuel range products, through a more detailed understanding and systematic studies of the effects of pretreatment procedures and promoters/binders (silica) on catalyst performance.

  7. Development of improved iron Fischer-Tropsch catalysts

    SciTech Connect

    Bukur, D.B.

    1992-01-10

    The objective of proposed research is development of catalysts with enhanced slurry phase activity and better selectivity to fuel range products, through a more detailed understanding and systematic studies of the effects of pretreatment procedures and promoters/binders (silica) on catalyst performance.

  8. Development of improved iron Fischer-Tropsch catalysts

    SciTech Connect

    Bukur, D.B.; Patel, S.A.

    1990-01-15

    The objective of proposed research is development of catalysts with enhanced slurry phase activity and better selectivity to fuel range products, through a more detailed understanding and systematic studies of the effects of pretreatment procedures and promoters/binders (silica) on catalyst performance.

  9. ɛ-Iron carbide as a low-temperature Fischer-Tropsch synthesis catalyst

    NASA Astrophysics Data System (ADS)

    Xu, Ke; Sun, Bo; Lin, Jun; Wen, Wen; Pei, Yan; Yan, Shirun; Qiao, Minghua; Zhang, Xiaoxin; Zong, Baoning

    2014-12-01

    ɛ-Iron carbide has been predicted to be promising for low-temperature Fischer-Tropsch synthesis (LTFTS) targeting liquid fuel production. However, directional carbidation of metallic iron to ɛ-iron carbide is challenging due to kinetic hindrance. Here we show how rapidly quenched skeletal iron featuring nanocrystalline dimensions, low coordination number and an expanded lattice may solve this problem. We find that the carbidation of rapidly quenched skeletal iron occurs readily in situ during LTFTS at 423-473 K, giving an ɛ-iron carbide-dominant catalyst that exhibits superior activity to literature iron and cobalt catalysts, and comparable to more expensive noble ruthenium catalyst, coupled with high selectivity to liquid fuels and robustness without the aid of electronic or structural promoters. This finding may permit the development of an advanced energy-efficient and clean fuel-oriented FTS process on the basis of a cost-effective iron catalyst.

  10. Role of copper promotion in precipitated iron Fischer-Tropsch catalysts

    SciTech Connect

    O`Brien, R.J.; Xu, L.; Davis, B.H.

    1996-10-01

    Slurry phase Fischer-Tropsch synthesis was conducted on precipitated iron-silicon catalysts. The affect of copper promotion on the activity and selectivity of carbon monoxide, hydrogen and syngas activated catalysts is presented. High activity and stability have been obtained for potassium promoted catalysts when operating at 270{degrees}C; however, it has been found that promotion with potassium and copper is essential to obtaining good activity in a wax producing mode at 230{degrees}C. Promotion with copper is critical to achieving good activity when pretreating catalysts with hydrogen or with syngas at high pressure. XRD and Mossbauer data indicate that copper facilitates the reduction of iron oxide to metallic iron and iron carbides during hydrogen and syngas pretreatments.

  11. Separation of Fischer-Tropsch Wax Products from Ultrafine Iron Catalyst Particles

    SciTech Connect

    Amitava Sarkar; James K. Neathery; Burtron H. Davis

    2006-12-31

    A fundamental filtration study was started to investigate the separation of Fischer-Tropsch Synthesis (FTS) liquids from iron-based catalyst particles. Slurry-phase FTS in slurry bubble column reactor systems is the preferred mode of operation since the reaction is highly exothermic. Consequently, heavy wax products in one approach may be separated from catalyst particles before being removed from the reactor system. Achieving an efficient wax product separation from iron-based catalysts is one of the most challenging technical problems associated with slurry-phase iron-based FTS and is a key factor for optimizing operating costs. The separation problem is further compounded by attrition of iron catalyst particles and the formation of ultra-fine particles.

  12. ε-Iron carbide as a low-temperature Fischer-Tropsch synthesis catalyst.

    PubMed

    Xu, Ke; Sun, Bo; Lin, Jun; Wen, Wen; Pei, Yan; Yan, Shirun; Qiao, Minghua; Zhang, Xiaoxin; Zong, Baoning

    2014-01-01

    ε-Iron carbide has been predicted to be promising for low-temperature Fischer-Tropsch synthesis (LTFTS) targeting liquid fuel production. However, directional carbidation of metallic iron to ε-iron carbide is challenging due to kinetic hindrance. Here we show how rapidly quenched skeletal iron featuring nanocrystalline dimensions, low coordination number and an expanded lattice may solve this problem. We find that the carbidation of rapidly quenched skeletal iron occurs readily in situ during LTFTS at 423-473 K, giving an ε-iron carbide-dominant catalyst that exhibits superior activity to literature iron and cobalt catalysts, and comparable to more expensive noble ruthenium catalyst, coupled with high selectivity to liquid fuels and robustness without the aid of electronic or structural promoters. This finding may permit the development of an advanced energy-efficient and clean fuel-oriented FTS process on the basis of a cost-effective iron catalyst. PMID:25503569

  13. Fischer-Tropsch Synthesis on Ceramic Monolith-Structured Catalysts

    SciTech Connect

    Wang, Yong; Liu, Wei

    2009-04-19

    This paper reports recent research results about impact of different catalyst bed configurations on FT reaction product distribution. A CoRe/γ-alumina catalyst is prepared in bulk particle form and tested in the packed bed reactor at a size of 60 to 100 mesh. The same catalyst is ball milled and coated on a ceramic monolith support structure of channel size about 1mm. The monolith catalyst module is tested in two different ways, as a whole piece and as well-defined channels. Steady-state reaction conversion is measured at various temperatures under constant H2/CO feed ratio of 2 and reactor pressure of 25 bar. Detailed product analysis is performed. Significant formation of wax is evident with the packed particle bed and with the monolith catalyst that is improperly packed. By contrast, the wax formation is not detected in the liquid product by confining the reactions inside the monolith channel. This study presents an important finding about the structured catalyst/reactor system that the product distribution highly depends on the way how the structured reactor is set up. Even if the same catalyst and same reaction conditions (T, P, H2/oil ratio) are used, hydrodynamics (or flow conditions) inside a structured channel can have a significant impact on the product distribution.

  14. Morphological transformation during activation and reaction of an iron Fischer-Tropsch catalyst

    SciTech Connect

    Jackson, N.B.; Kohler, S.; Harrington, M.

    1995-12-31

    The purpose of this project is to support the development of slurry-phase bubble column processes being studied at the La Porte Alternative Fuel Development Unit. This paper describes the aspects of Sandia`s recent work regarding the advancement and understanding of the iron catalyst used in the slurry phase process. A number of techniques were used to understand the chemical and physical effects of pretreatment and reaction on the attrition and carbon deposition characteristics of iron catalysts. Unless otherwise stated, the data discussed was derived form experiments carried out on the catalyst chosen for the summer 1994 Fischer-Tropsch run at LaPorte, UCI 1185-78-370, (an L 3950 type) that is 88% Fe{sub 2}O{sub 3}, 11% CuO, and 0.052%K{sub 2}O.

  15. Metal organic framework-mediated synthesis of highly active and stable Fischer-Tropsch catalysts.

    PubMed

    Santos, Vera P; Wezendonk, Tim A; Jaén, Juan José Delgado; Dugulan, A Iulian; Nasalevich, Maxim A; Islam, Husn-Ubayda; Chojecki, Adam; Sartipi, Sina; Sun, Xiaohui; Hakeem, Abrar A; Koeken, Ard C J; Ruitenbeek, Matthijs; Davidian, Thomas; Meima, Garry R; Sankar, Gopinathan; Kapteijn, Freek; Makkee, Michiel; Gascon, Jorge

    2015-01-01

    Depletion of crude oil resources and environmental concerns have driven a worldwide research on alternative processes for the production of commodity chemicals. Fischer-Tropsch synthesis is a process for flexible production of key chemicals from synthesis gas originating from non-petroleum-based sources. Although the use of iron-based catalysts would be preferred over the widely used cobalt, manufacturing methods that prevent their fast deactivation because of sintering, carbon deposition and phase changes have proven challenging. Here we present a strategy to produce highly dispersed iron carbides embedded in a matrix of porous carbon. Very high iron loadings (>40 wt %) are achieved while maintaining an optimal dispersion of the active iron carbide phase when a metal organic framework is used as catalyst precursor. The unique iron spatial confinement and the absence of large iron particles in the obtained solids minimize catalyst deactivation, resulting in high active and stable operation. PMID:25740709

  16. Metal organic framework-mediated synthesis of highly active and stable Fischer-Tropsch catalysts

    NASA Astrophysics Data System (ADS)

    Santos, Vera P.; Wezendonk, Tim A.; Jaén, Juan José Delgado; Dugulan, A. Iulian; Nasalevich, Maxim A.; Islam, Husn-Ubayda; Chojecki, Adam; Sartipi, Sina; Sun, Xiaohui; Hakeem, Abrar A.; Koeken, Ard C. J.; Ruitenbeek, Matthijs; Davidian, Thomas; Meima, Garry R.; Sankar, Gopinathan; Kapteijn, Freek; Makkee, Michiel; Gascon, Jorge

    2015-03-01

    Depletion of crude oil resources and environmental concerns have driven a worldwide research on alternative processes for the production of commodity chemicals. Fischer-Tropsch synthesis is a process for flexible production of key chemicals from synthesis gas originating from non-petroleum-based sources. Although the use of iron-based catalysts would be preferred over the widely used cobalt, manufacturing methods that prevent their fast deactivation because of sintering, carbon deposition and phase changes have proven challenging. Here we present a strategy to produce highly dispersed iron carbides embedded in a matrix of porous carbon. Very high iron loadings (>40 wt %) are achieved while maintaining an optimal dispersion of the active iron carbide phase when a metal organic framework is used as catalyst precursor. The unique iron spatial confinement and the absence of large iron particles in the obtained solids minimize catalyst deactivation, resulting in high active and stable operation.

  17. Fischer-Tropsch reaction studies with supported ruthenium catalysts

    SciTech Connect

    Everson, R.C.; Mulder, H. )

    1993-09-01

    An investigation was undertaken to examine the production of low molecular weight alkenes (C[sub 2][sup =] to C[sup =][sub 4]) and high molecular weight hydrocarbons (C[sub 5]+) from synthesis gas in a fixed bed reactor with supported ruthenium catalyst. The catalyst used consisted of 0.5% ruthenium on gamma-alumina with a 43% metal dispersion. An experimental reactor consisting of a single 12.5-mm-diameter stainless-steel tube with catalyst packings up to 1 m long, surrounded by an aluminium block with heating elements and an outer insulating ceramic block was used. The effect of temperature, synthesis gas composition (CO/H[sub 2]), weight hourly space velocity (WHSV), and bed length on carbon monoxide conversion and selectivity was examined and results are reported. The presence of secondary reactions consisting of hydrogenation and chain growth involving alkenes along the reactor bed was observed. These reactions favour the formation of alkanes and high molecular weight hydrocarbons. The alkene to alkane ratio in the product can be increased by restricting the hydrogenation reaction with the use of a synthesis gas mixture with a high carbon monoxide to hydrogen ratio.

  18. Technology development for iron Fischer-Tropsch catalysis. Quarterly technical progress report, 1996

    SciTech Connect

    Davis, B.H.

    1996-11-01

    The objective of this research project is to develop the technology for the production of physically robust iron-based Fischer-Tropsch catalysts that have suitable activity, selectivity and stability to be used in the slurry phase synthesis reactor development. The catalysts that are developed shall be suitable for testing in the Advanced Fuels Development Facility at LaPorte, Texas, to produce either low- or high-alpha product distributions. Previous work by the offeror has produced a catalyst formulation that is 1.5 times as active as the ``standard-catalyst`` developed by German workers for slurry phase synthesis. The proposed work will optimize the catalyst composition and pretreatment operation for this low-alpha catalyst. In parallel, work will be conducted to design a high-alpha iron catalyst this is suitable for slurry phase synthesis. Studies will be conducted to define the chemical phases present at various stages of the pretreatment and synthesis stages and to define the course of these changes. The oxidation/reduction cycles that are anticipated to occur in large, commercial reactors will be studied at the laboratory scale. Catalyst performance will be determined for catalysts synthesized in this program for activity, select and aging characteristics. The research is divided into four major topical areas: (a) catalyst preparation and characterization, (b) product characterization, (c) reactor operations, and (d) data assessment. Accomplishments for this period are described.

  19. Activation and promotion studies in a mixed slurry reactor with an iron-manganese Fischer-Tropsch catalyst

    SciTech Connect

    Pennline, H.W.; Zarochak, M.F.; Stencel, J.M.; Diehl, J.R.

    1987-03-01

    Synthesis gas was reacted over a coprecipitated iron-manganese Fischer-Tropsch catalyst in a slurry reactor. The effect of various activation parameters - temperature, pressure, and gas composition - on subsequent catalyst activity and product selectivity was investigated. The gas composition had the most dramatic effect on the catalyst activation and the ensuing synthesis gas conversion. The effect of potassium promotion on catalyst activity and product selectivity was also studied in slurry reactor tests.

  20. Titania-supported bimetallic catalysts combined with HZSM-5 for Fischer-Tropsch synthesis

    SciTech Connect

    Jothimurugesan, K.; Gangwal, S.K.

    1998-04-01

    The Fischer-Tropsch synthesis (FTS) can convert coal or natural gas derived synthesis gas (CO + H{sub 2}) to liquid fuels and high-value chemicals. Fischer-Tropsch synthesis was studied in a fixed-bed reactor over single-metal and bimetallic alloy catalysts, selected from Co, Ni, and Fe, supported on TiO{sub 2} at a total metal loading of 10 wt%. The catalysts, prepared by incipient wetness impregnation using nitrate precursors, were tested as is and in combination with a HZSM-5 zeolite. The test conditions were 1 MPa, 250 C, H{sub 2}/CO = 1, and weight hourly space velocity (WHSV) = 0.77 h{sup {minus}1}. Alloying of metals resulted in a significant enhancement in CO conversion without an increase in methane selectivity. A 50:50 weight ratio Co-Ni catalyst physically mixed with HZSM-5 (5% Co-5% Ni/TiO{sub 2} + HZSM-5) gave the highest CO conversion (45.2%) at the conditions tested. This compares to conversion of 8.9% and 10.5% with Co-only and Ni-only catalysts, respectively. Mixing the Co-Ni catalyst with HZSM-5 resulted in a significant reduction in methane selectivity and a significant increase in C{sub 4}{sup +} selectivity. The aromatic fraction increased from 1.5 to 8.1 wt%, the C{sub 2}{sup +} olefins were nearly eliminated, and i-C{sub 4}H{sub 10} increased from 2.3 to 58.5 wt % in the C{sub 4} fraction.

  1. Mössbauer study of CO-precipitated Fischer-Tropsch iron catalysts

    NASA Astrophysics Data System (ADS)

    Rao, K. R. P. M.; Huggins, Frank E.; Mahajan, Vikram; Huffman, Gerald P.; Bukur, D. B.; Rao, V. U. S.

    1994-12-01

    Mössbauer spectroscopy studies of precipitated Fischer-Tropsch (FT) iron catalysts, viz. 100 Fe/5 Cu/4.2 K/ x SiO2, where x=0,8, 16, 24, 25, 40, or 100, have shown that reduction of the oxide precursor in CO gives rise to χ-carbide Fe5C2 whose amount decreases with an increase of SiO2 content. The χ-carbide is converted into magnetite Fe3O4 while catalyzing the FT synthesis reaction. A correlation between FT activity and the content of χ-carbide in the catalysts was found, which indicated that χ-carbide is active for FT synthesis reaction.

  2. Slurry phase Fischer-Tropsch synthesis: Cobalt plus a water-gas shift catalyst

    SciTech Connect

    Chanenchuk, C.A.; Yates, I.C.; Satterfield, C.N.

    1990-01-01

    Experiments to study the cobalt-catalyzed and iron-catalyzed reactions of light 1-alkenes added to synthesis gas have been performed and analyzed. On cobalt, data have been obtained at 220{degrees}C, 0.45 to 1.48 MPA and a synthesis gas flow rate between 0.015 and 0.030 Nl/gcat/min with H{sub 2}/CO feeds of 1.45 to 2.25. On fused iron, data were collected at 248{degrees}C, 0.79 to 1.48 MPa and a synthesis gas flow rate between 0.005 and 0.030 Nl/gcat/min of H{sub 2}/CO feeds of 0.5 to 1.5 C{sub 2}H{sub 4}, C{sub 3}H{sub 6}, and 1-C{sub 4}H{sub 8} were added to the synthesis gas feed in concentrations ranging from 0.5 to 1.2 mol. % of total feed. 1-Alkenes incorporate into growing chains on the catalyst surface of both catalysts, probably by initiating and/or terminating the chain growth process. Only ethene is believed to propagate chain growth significantly. The propensity of the 1-alkenes to incorporate decreases with increasing carbon number of the 1-alkene. The double-{alpha} behavior which is exhibited by most Fischer-Tropsch catalysts can be explained as the sum of two growth processes, one stepwise single-carbon growth and the other 1-alkene incorporation. Both alkene addition study data and the effects of process variables on the selectivity of Fischer-Tropsch catalysts can be explained within the framework of this theory. 19 refs., 12 figs., 2 tabs.

  3. Nanoscale attrition during activation of precipitated iron Fischer- Tropsch catalysts: Implications for catalyst design

    SciTech Connect

    Datye, A.K.; Shroff, M.D.; Jin, Y.; Brooks, R.P.; Wilder, J.A.; Harrington, M.S.; Sault, A.G.; Jackson, N.B.

    1996-06-01

    This work has shown that the kaolin binder that has been used in commercial Fischer-Tropsch Synthesis catalysts doe not offer any significant attrition resistance. This is due in part to its morphology (plate-like) and to its particle size being much greater than the primary crystallite size of the iron oxide catalyst. From a microscopic examination of these catalysts, it appears that if the nanoscale attrition of the iron catalyst is to be avoided, the iron must be well dispersed on the binder, and the binder must provide an interlocking microstructure that provides strength and stability to the 30-70 {mu}m agglomerates. The study of Fe/SiO{sub 2} catalysts has shown that co-precipitation of the iron and silica leads to formation of an amorphous glassy phase which is difficult to reduce even at 723K. On the other hand, when the iron was precipitated on a preformed silica, 25-40% of the iron could be reduced and carbided. The supported iron catalyst, after reduction, formed 15-20 nm iron carbide particles that look very similar to those on the unsupported catalyst. The major difference is these nanometer sized particles are anchored on a support and therefore would not be expected to breakup further and contribute to the fines generated as catalyst attrition proceeds. However, since only a fraction of the silica-supported iron can be reduced to the active carbide phase, our present efforts are devoted to moderating the Fe/SiO{sub 2} interaction by introducing an interfacial oxide phase. We are also studying the role of added Cu on the ease of reducibility of Fe/SiO{sub 2}. The implication of this work is that other binder materials should be explored that have a morphology that can strengthen the agglomerates and minimize the Fe-SiO{sub 2} interfacial reactions. This work is presently underway in our laboratory.

  4. Preparation of Fischer-Tropsch catalysts from cobalt/iron hydrotalcites

    SciTech Connect

    Howard, B.H.; Boff, J.J.; Zarochak, M.F.

    1995-12-31

    Compounds with the (hydrotalcites) have properties that make them attractive as precursors for Fischer-Tropsch catalysts. A series of single-phase hydrotalcites with cobalt/iron atom ratios ranging from 75/25 to 25/75 has been synthesized. Mixed cobalt/iron oxides have been prepared from these hydrotalcites by controlled thermal decomposition. Thermal decomposition at temperatures below 600 {degrees}C typically produced a single-phase mixed metal oxide with a spinel structure. The BET surface areas of the spinal samples have been found to be as high as about 150 m{sup 2}/g. Appropriate reducing pretreatments have been developed for several of these spinels and their activity, selectivity, and activity and selectivity maintenance have been examined at 13 MPa in a fixed-bed microreactor.

  5. Isotopic tracer studies of Fischer-Tropsch Synthesis over Ru/TiO sub 2 catalysts

    SciTech Connect

    Krishna, K.R.

    1992-01-01

    Fischer-Tropsch synthesis is a process in which CO and H{sub 2} react to give predominantly liquid hydrocarbons. The reaction can be considered a special type of polymerization in which the monomer is produced in situ, and chain growth occurs by a sequence of independently repeated additions of the monomer to the growing chain. A investigation has been conducted to study the CO hydrogenation reaction in order to better understand catalyst deactivation and the elementary surface processes involved in chain growth. Isotopic tracers are used in conjunction with transient-response techniques in this study of Fischer-Tropsch synthesis over Ru/TiO{sub 2} catalysts. Experiments are conducted at a total pressure of 1 atmosphere, reaction temperatures of 453--498 K and D{sub 2}/CO (or H{sub 2}/CO) ratios of 2--5. Synthesis products are analyzed by gas chromatography or isotope-ratio gas chromatography-mass spectrometry. Rate constants for chain initiation, propagation and termination are evaluated under steady-state reaction conditions by using transients in isotopic composition. The activation energy for chain termination is much higher than that for propagation, accounting for the observed decrease in the chain growth parameter are also estimated. Coverages by reaction intermediates are also estimated. When small amounts of {sup 12}C-labelled ethylene are added to {sup 13}CO/H{sub 2} synthesis gas, ethylene acts as the sole chain initiator. Ethylene-derived carbon also accounts for 45% of the C{sub 1} monomer pool. 102 refs., 29 figs., 11 tabs.

  6. Isotopic tracer studies of Fischer-Tropsch Synthesis over Ru/TiO{sub 2} catalysts

    SciTech Connect

    Krishna, K.R.

    1992-01-01

    Fischer-Tropsch synthesis is a process in which CO and H{sub 2} react to give predominantly liquid hydrocarbons. The reaction can be considered a special type of polymerization in which the monomer is produced in situ, and chain growth occurs by a sequence of independently repeated additions of the monomer to the growing chain. A investigation has been conducted to study the CO hydrogenation reaction in order to better understand catalyst deactivation and the elementary surface processes involved in chain growth. Isotopic tracers are used in conjunction with transient-response techniques in this study of Fischer-Tropsch synthesis over Ru/TiO{sub 2} catalysts. Experiments are conducted at a total pressure of 1 atmosphere, reaction temperatures of 453--498 K and D{sub 2}/CO (or H{sub 2}/CO) ratios of 2--5. Synthesis products are analyzed by gas chromatography or isotope-ratio gas chromatography-mass spectrometry. Rate constants for chain initiation, propagation and termination are evaluated under steady-state reaction conditions by using transients in isotopic composition. The activation energy for chain termination is much higher than that for propagation, accounting for the observed decrease in the chain growth parameter are also estimated. Coverages by reaction intermediates are also estimated. When small amounts of {sup 12}C-labelled ethylene are added to {sup 13}CO/H{sub 2} synthesis gas, ethylene acts as the sole chain initiator. Ethylene-derived carbon also accounts for 45% of the C{sub 1} monomer pool. 102 refs., 29 figs., 11 tabs.

  7. Development of a stable cobalt-ruthenium Fischer-Tropsch catalyst

    SciTech Connect

    Abrevaya, H.

    1991-01-01

    The objective of this contract is to examine the relationship between catalytic properties and the function of cobalt Fischer-Tropsch catalysts and to apply this fundamental knowledge to the development of a stable cobalt-based catalyst with a low methane-plus-ethane selectivity for use in slurry reactors. An experimental cobalt catalyst 585R2723 was tested three times in the fixed-bed reactor. The objective of the tests was to identify suitable testing conditions for screening catalyst. The {alpha}-alumina was determined to be a suitable diluent medium for controlling the catalyst bed temperature close to the inlet temperature. With 13 g of catalyst and 155 g of diluent, the catalyst maximum temperature were within 2{degree}C from the inlet temperatures. As a result of this work, 210{degree}C and 21 atm were shown to result in low methane selectivity and were used as initial conditions in the catalyst screening test. Ethane, which along with methane is undesirable, is typically produced with low selectivity and follows the same trend as methane. Other work reported here indicated that methane selectivity increases with increasing temperature but is not excessively high at 230{degree}C. Consequently, the catalyst screening test should include an evaluation of the catalyst performance at 230{degree}C. During Run 67, the increase in temperature from 210{degree}C to 230{degree}C was initiated at 30 hours on-stream.

  8. Separation of Fischer-Tropsch catalyst/wax mixtures using dense gas extraction

    SciTech Connect

    Eyring, M.W.; Rohar, P.C.; Hickey, R.F.; White, C.M.; Quiring, M.S.

    1995-12-31

    The separation of a Fischer-Tropsch catalyst from wax products is an important issue when the synthesis is conducted in a slurry bubble column reactor. This paper describes a new technique based on dense gas extraction of the soluble hydrocarbon components from the insoluble catalyst particles using light hydrocarbons as propane, butane, and pentane an the solvent. The extractions were conducted in a continuous unit operated near the critical point of the extraction gas on a catalyst/wax mixture containing about 4.91 wt% catalyst. The catalyst-free wax was collected in the second stage collector while the catalyst and some insoluble wax components were collected in the first stage collector. The yield of catalyst-free wax was about 60 wt% of the food mixture. The catalyst content of the catalyst/wax mixture in the first stage was about 14.8 wt%. The catalyst content in the second stage collector was less than 1 part in 100,000.

  9. Separation of Fischer-Tropsch catalyst/wax mixtures using dense gas extraction

    SciTech Connect

    Eyring, M.W.; Rohar, P.C.; Hickey, R.F.

    1995-12-01

    The separation of a Fischer-Tropsch catalyst from wax products is an important issue when the synthesis is conducted in a slurry bubble column reactor. This paper describes a new technique based on dense gas extraction of the soluble hydrocarbon components from the insoluble catalyst particles using light hydrocarbons as propane, butane, and pentane as the solvent. The extractions were conducted in a continuous unit operated near the critical point of the extraction gas on a catalyst/wax mixture containing about 4.91 wt% catalyst. The catalyst-free wax was collected in the second stage collector while the catalyst and some insoluble wax components were collected in the first stage collector. The yield of catalyst-free wax was about 60 wt% of the feed mixture. The catalyst content of the catalyst/wax mixture in the first stage was about 14.8 wt%. The catalyst content in the second stage collector was less than 1 part in 100,000.

  10. Slurry phase Fischer-Tropsch synthesis: Cobalt plus a water-gas shift catalyst

    SciTech Connect

    Yates, I.C.; Satterfield, C.N.

    1988-01-01

    A cobalt Fischer-Tropsch catalyst (CO/MgO/silica) was reduced and slurried in combination with reduced Cu/ZnO/Al[sub 2]0[sub 3] water-gas-shift catalyst. Combined catalyst system was run at fixed process conditions for more than 400 hours. The system showed stable selectivity. The Cu/ZnO/Al[sub 2]0[sub 3] water-gas-shift catalyst remained reasonably active in the presence of the cobalt catalyst. Hydrocarbon selectivity of the cobalt and Cu/ZnO/Al[sub 2]0[sub 3] catalyst system compared favorably to selectivity of iron-based catalysts. Methane selectivity was slightly higher for the cobalt-based system, but C[sub 5][sup +] selectivity was essentially the same. The hydrocarbon product distribution appeared to exhibit a double-a behavior. a[sub 1] was near 0.80 which is higher than that of iron catalysts, while a[sub 2] was calculated to be 0.86 which is somewhat lower than would be typical for an iron-based catalyst.

  11. An innovative catalyst system for slurry-phase Fischer-Tropsch synthesis: Cobalt plus a water-gas-shift catalyst

    SciTech Connect

    Satterfield, C.N.; Yates, I.C.; Chanenchuk, C.

    1991-07-01

    The feasibility of using a mechanical mixture of a Co/MgO/SiO{sub 2} Fischer-Tropsch catalyst and a Cu-ZnO/Al{sub 2}O{sub 3} water-gas-shift (WGS) catalyst for hydrocarbon synthesis in a slurry reactor has been established. Such a mixture can combine the superior product distribution from cobalt with the high activity for the WGS reaction characteristic of iron. Weight ratios of Co/MgO/SiO{sub 2} to Cu-ZnO/Al{sub 2}O{sub 3} of 0.27 and 0.51 for the two catalysts were studied at 240{degrees}C, 0.79 MPa, and in situ H{sub 2}/CO ratios between 0.8 and 3.0. Each catalyst mixture showed stable Fischer-Tropsch activity for about 400 hours-on-stream at a level comparable to the cobalt catalyst operating alone. The Cu-ZnO/Al{sub 2}O{sub 3} catalyst exhibited a very slow loss of activity under these conditions, but when operated alone it was stable in a slurry reactor at 200--220{degrees}C, 0.79--1.48 MPa, and H{sub 2}/CO in situ ratios between 1.0 and 2.0. The presence of the water-gas-shift catalyst did not affect the long-term stability of the primary Fischer-Tropsch selectivity, but did increase the extent of secondary reactions, such as l-alkene hydrogenation and isomerization.

  12. Preparation of a novel structured catalyst based on aligned carbon nanotube arrays for a microchannel Fischer-Tropsch synthesis reactor

    SciTech Connect

    Chin, Ya-Huei; Hu, Jianli; Cao, Chunshe; Gao, Yufei; Wang, Yong

    2005-12-15

    A novel catalyst microstructure based on aligned multiwall carbon nanotube arrays was synthesized. Its advanced heat and mass transport characteristics coupled with high surface area led to superior performances for Fischer-Tropsch synthesis in a microchannel chemical reactor. The fabrication of such a novel catalyst structure first involved metalorganic chemical vapor deposition (MOCVD) growth of a dense Al2O3 thin film over FeCrAlY foam substrate to enhance adhesion between catalyst layer and metal substrate. Aligned arrays of multiwall carbon nanotubes were grown over the substrate by catalytic decomposition of ethylene. These nanotube bundles were directly attached to the FeCrAlY substrate through a thin layer of oxide thin film. When the outer surfaces of nanobundles were coated with a catalyst layer, a unique hierarchical catalyst structure with nanoporous interstitials between the bundles was created. Thus, engineered catalysts based on such a novel hierarchical structure minimizes mass transfer encountered in the gas-liquid-solid three phase reactions. In addition, high thermal conductivity of carbon nanotube and the direct attachment of these nanobundles to the metal foam allow efficient heat removal from catalytic sites. The advanced heat and mass transfer on this novel structured catalyst was demonstrated in Fischer-Tropsch synthesis in a microchannel fixed bed reactor. The presence of carbon nanotube arrays improved dispersion of active metals and reduced mass transfer limitation, leading to a factor of four enhancement of Fischer-Tropsch synthesis activity. The improved temperature control with the carbon nanotube arrays also allows the Fischer-Tropsch synthesis being operated at temperatures as high as 265 C without reaction runaway favoring methane formation.

  13. Fischer-Tropsch synthesis in slurry-reactor systems. Quarterly report, August 1, 1981-October 31, 1981

    SciTech Connect

    Satterfield, C.N.; Bartos, T.; Huff, G.A. Jr.; Stenger, H.

    1981-01-01

    A large quantity of data were obtained with the fused iron catalyst under intrinsic kinetic conditions, covering for the first time 50 and 200 psi. These data are being analyzed for information about overall rates and product selectivity. Preliminary conclusions about a rate model are presented. Study of the effects of suspended solids on gas-liquid mass transfer was started. Most previous information is on aqueous systems, which is not readily translatable into predicted effects in organic liquids such as Fischer-Tropsch liquids. The most promising and useful method at present appears to be a chemical method based on absorption of CO/sub 2/ into an organic solution of an amine. A paper on a stirred-autoclave apparatus for studying the Fischer-Tropsch synthesis in a slurry bed in included.

  14. Highly active and stable iron Fischer-Tropsch catalyst for synthesis gas conversion to liquid fuels

    SciTech Connect

    Bukur, D.B.; Lang, X.

    1999-09-01

    A precipitated iron Fischer-Tropsch (F-T) catalyst (100 Fe/3 Cu/4 K/16 SiO{sub 2} on mass basis) was tested in a stirred tank slurry reactor under reaction conditions representative of industrial practice using CO-rich synthesis gas (260 C, 1.5--2.2 MPa, H{sub 2}/CO = 2/3). Repeatability of performance and reproducibility of catalyst preparation procedure were successfully demonstrated on a laboratory scale. Catalyst productivity was increased by operating at higher synthesis pressure while maintaining a constant contact time in the reactor and through the use of different catalyst pretreatment procedures. In one of the tests (run SA-2186), the catalyst productivity was 0.86 (g hydrocarbons/g Fe/h) at syngas conversion of 79%, methane selectivity of 3% (weight percent of total hydrocarbons produced), and C{sub 5}+ hydrocarbon selectivity of 83 wt %. This represents a substantial improvement in productivity in comparison to state-of-the-art iron F-T catalysts. This catalyst is ideally suited for production of high-quality diesel fuels and C{sub 2}-c{sub 4} olefins from a coal-derived synthesis gas.

  15. Compositional aspects of iron Fischer-Tropsch catalysts: an x-ray photoelectron

    SciTech Connect

    Kuivila, C.S.

    1987-01-01

    Iron catalysts employed in the Fischer-Tropsch synthesis consist of metallic, carbide, and oxide phases. The catalytic and compositional behavior of prereduced and unreduced iron catalysts were investigated in this study. Catalytic behavior was evaluated by measuring the rates of hydrocarbon formation in a 3:1 H/sub 2//CO mixture at one atmosphere and 250/sup 0/C. Iron phases which evolved near the catalyst surfaces were characterized by x-ray photoelectron spectroscopy, and bulk phases present following the synthesis reactions were determined by Mossbauer spectroscopy. At low conversion levels, prereduced iron catalysts were gradually converted to iron carbide. At total CO conversion levels in the range of 30 to 40%, prereduced catalysts were converted primarily to iron carbide, although some surface oxide phases also formed. Unreduced Fe/sub 2/O/sub 3/ exhibited no initial synthesis activity, but underwent gradual activation and eventually became more active than the prereduced catalysts. The various phases of the iron catalysts were related to varying olefin production rates.

  16. Compositional aspect of iron Fischer-Tropsch catalyst: An XPS/reaction study

    SciTech Connect

    Kuivila, C.S.; Stair, P.C.; Butt, J.B. )

    1989-08-01

    The catalytic and compositional behaviors of prereduced and unreduced iron catalysts for Fischer-Tropsch synthesis were investigated. Catalytic behavior was evaluated by measuring rates of hydrocarbon formation 3:1 H{sub 2}:CO mixture at 1 atm and 250C. Iron phases which evolved near the catalyst surfaces were characterized by X-ray photoelectron spectroscopy, and bulk phases present following reaction were determined by Moessbauer spectroscopy. At low conversion levels the prereduced catalyst was gradually converted to iron carbide with no significant oxide phase formed. Synthesis activities increased initially with the formation of active surface carbon, but eventually lost some activity due to graphitic carbon formation. At higher conversions, the prereduced catalyst showed some formation of surface oxide phases and an inhibition of the synthesis rate due to water adsorption. Surface carbon accumulation was also suppressed under these conditions. Unreduced Fe{sub 2}O{sub 3} showed no initial synthesis activity, but underwent a gradual activation to become even more active than the prereduced catalyst. The oxide catalyst was eventually completely reduced to Fe{sub 3}O{sub 4}, and any metallic phase formed was rapidly converted to iron carbide. Compared to reduced materials, the oxide catalyst accumulated considerably less surface carbon and showed no loss of activity for reaction times up to 48 h. XPS analysis suggests that Fe{sub 3}O{sub 4} is active for synthesis.

  17. Novel Fischer-Tropsch slurry catalysts and process concepts for selective transportation fuel production: Final report

    SciTech Connect

    Withers, H.P. Jr.; Eliezer, K.F.; Mitchell, J.W.

    1987-12-01

    The preparation, characterization and performance of cobalt and ruthenium carbonyl cluster-based catalysts for use in slurry-phase Fischer-Tropsch (FT) technology was investigated. The use of metal carbonyls as active metal precursor allows for the possible control of metal particle size on the support surface and thus offers the potential for better control of activity and selectivity of the FT reaction. Accomplishments included reproducible catalyst preparation, improvements in activity by use of a silica support, understanding diffeences between nitrate and carbonyl precursors, a nd good activity maintenance in the slurry reactor. A CO/sub 2/(CO)/sub 8/Zr(OPr)/sub 4/SiO/sub 2/ catalyst (3.5% CO, 6.6% Zr) was developed as the most active system in the slurry reactor and also gave the best liquid fuel selectivity. Silica support provided the highest catalyst activities. This catalyst was successfully tested in an extended slurry-phase run that achieved 6 months on stream with a 10% loss in activity. Ru catalysts showed the highest activity in the fixed-bed reactor but deactivated rapidly in the slurry reactor. In the analysis of the kinetic data, catalyst deactivation was assumed to proceed linearly between baseline experients at fixed temperture. Causes of the deactivation are not fully understood. 27 refs., 37 figs., 20 tabs.

  18. Fischer-Tropsch Cobalt Catalyst Activation and Handling Through Wax Enclosure Methods

    NASA Technical Reports Server (NTRS)

    Klettlinger, Jennifer L. S.; Yen, Chia H.; Nakley, Leah M.; Surgenor, Angela D.

    2016-01-01

    Fischer-Tropsch (F-T) synthesis is considered a gas to liquid process which converts syn-gas, a gaseous mixture of hydrogen and carbon monoxide, into liquids of various hydrocarbon chain length and product distributions. Cobalt based catalysts are used in F-T synthesis and are the focus of this paper. One key concern with handling cobalt based catalysts is that the active form of catalyst is in a reduced state, metallic cobalt, which oxidizes readily in air. In laboratory experiments, the precursor cobalt oxide catalyst is activated in a fixed bed at 350 ?C then transferred into a continuous stirred tank reactor (CSTR) with inert gas. NASA has developed a process which involves the enclosure of active cobalt catalyst in a wax mold to prevent oxidation during storage and handling. This improved method allows for precise catalyst loading and delivery into a CSTR. Preliminary results indicate similar activity levels in the F-T reaction in comparison to the direct injection method. The work in this paper was supported by the NASA Fundamental Aeronautics Subsonics Fixed Wing Project.

  19. Synthesis of octane enhancers during slurry-phase Fischer-Tropsch. Quarterly technical progress report No. 6, January 1, 1992--March 31, 1992

    SciTech Connect

    Marcelin, G.

    1992-06-24

    The objective of this project is to investigate three possible routes to the formation of ethers, in particular methyl tert-butyl ether (MTBE), during slurry phase Fischer-Tropsch reaction. The three reaction schemes to be investigated are: (1) Addition of isobutylene during the formation of methanol and/or higher alcohols directly from CO and H{sub 2} during slurry-phase Fischer-Tropsch. (2) Addition of isobutylene to FT liquid products including alcohols in a slurry-phase reactor containing an MTBE or other acid catalyst. (3) Addition of methanol to slurry phase FT synthesis making iso-olefins. During the sixth quarter we completed the construction of the slurry bubble column reactor (SBCR), conducted initial shake-down experiments in a cold-flow mode, and finalized the selection process of the acid catalysts for conversion of syngas-produced alcohols and isobutylene to MTBE (scheme 2). Tasks 3, 4, and 5 are awaiting complete implementation of the SBCR system.

  20. Bridging the pressure and material gap in heterogeneous catalysis: cobalt Fischer-Tropsch catalysts from surface science to industrial application.

    PubMed

    Oosterbeek, Heiko

    2007-07-21

    The Fischer-Tropsch (FT) process is the heart of many natural gas conversion processes as it enables the conversion of a mixture of CO and H(2) into valuable long-chain hydrocarbons. Here we report on the use of state-of-the-art surface science techniques to obtain information on the relationship between the surface atomic structure of model catalysts and their performance in the Fischer-Tropsch reaction. Cobalt single crystals and polycrystals were modified with non-reducible oxides as to resemble industrial catalysts. Reflection absorption infrared spectroscopy was used for examining the CO adsorption behaviour at room temperature as well as at 493 K at CO pressures spanning 10(-7) to 300 mbar on both (modified) Co single/polycrystals and an industrial catalyst. Polarization modulation was applied to cancel the CO gas phase absorption. Subsequently, they were subjected to reaction tests in the same apparatus at 1 bar and 493 K. This allowed us to close the material, pressure and instrument gap in the field of Fischer-Tropsch synthesis on cobalt-based catalysts. PMID:17612722

  1. Nanocrystalline Iron-Ore-Based Catalysts for Fischer-Tropsch Synthesis.

    PubMed

    Yong, Seok; Park, Ji Chan; Lee, Ho-Tae; Yang, Jung-Il; Hong, SungJun; Jung, Heon; Chun, Dong Hyun

    2016-02-01

    Nanocrystalline iron ore particles were fabricated by a wet-milling process using an Ultra Apex Mill, after which they were used as raw materials of iron-based catalysts for low-temperature Fischer-Tropsch synthesis (FTS) below 280 degrees C, which usually requires catalysts with a high surface area, a large pore volume, and a small crystallite size. The wet-milling process using the Ultra Apex Mill effectively destroyed the initial crystallite structure of the natural iron ores of several tens to hundreds of nanometers in size, resulting in the generation of nanocrystalline iron ore particles with a high surface area and a large pore volume. The iron-ore-based catalysts prepared from the nanocrystalline iron ore particles effectively catalyzed the low-temperature FTS, displaying a high CO conversion (about 90%) and good C5+ hydrocarbon productivity (about 0.22 g/g(cat)(-h)). This demonstrates the feasibility of using the iron-ore-based catalysts as inexpensive and disposable catalysts for the low-temperature FTS. PMID:27433720

  2. Improved Fischer-Tropsch catalysts for indirect coal liquefaction. Final report

    SciTech Connect

    Wilson, R.B. Jr.; Tong, G.T.; Chan, Y.W.; Huang, H.W.; McCarty, J.G.

    1989-02-01

    The Fischer-Tropsch synthesis (FTS)reaction is the established technology for the production of liquid fuels from coal by an indirect route using coal-derived syngas (CO + H{sub 2}). Modern FTS catalysts are potassium- and copper-promoted iron preparations. These catalysts exhibit moderate activity with carbon monoxide-rich feedstocks such as the syngas produced by advanced coal gasification processes. However, the relatively large yields of by-product methane and high-molecular-weight hydrocarbon waxes detract from the production of desired liquid products in the C{sub 5}-C{sub 16} range needed for motor and aviation fuel. The goal of this program is to decrease undesirable portions of the FTS hydrocarbon yield by altering the Schultz-Flory polymerization product distribution through design and formulation of improved catalysts. Two approaches were taken: (1) reducing the yield of high-molecular-weight hydrocarbon waxes by using highly dispersed catalysts produced from surface-confined multiatomic clusters on acid supports and (2) suppressing methane production by uniformly pretreating active, selective conventional FTS catalysts with submonolayer levels of sulfur.

  3. Slurry-phase Fischer-Tropsch synthesis and kinetic studies over supported cobalt carbonyl derived catalysts

    SciTech Connect

    Withers, H.P. Jr.; Eliezer, K.F.; Mitchell, J.W. )

    1990-09-01

    This paper reports the preparation characterization, and performance of cobalt carbonyl cluster based catalysts for use in slurry-phase Fischer--Tropsch (FT) technology investigated. Using metal carbonyls as active metal precursors allows for the control of metal particle size on the support surface, thus offering the potential for better control of activity and selectivity of the FT reaction. Silica as the support provided the highest catalyst activities. A Co{sub 2}(CO){sub 8}/Zr(OPr){sub 4}/SiO{sub 2} catalyst (3.5% cobalt, 6.6% zirconium) was developed as the most active system in the FT slurry reactor and also gave the best liquid fuel selectivity. Selectivity patterns correlated to the Schulz--Flory prediction. These catalysts exhibited low water/gas shift activity. Diesel fuel product produced by this catalyst was high quality. A kinetic expression that took water inhibition into account was verified, yielding an activation energy of 97 kJ/mol for syngas conversion ranging from 34% to 71% at 240--280{degrees} C.

  4. SEPARATION OF FISCHER-TROPSCH WAX PRODUCTS FROM ULTRAFINE IRON CATALYST PARTICLES

    SciTech Connect

    James K. Neathery; Gary Jacobs; Burtron H. Davis

    2004-03-31

    In this reporting period, a fundamental filtration study was started to investigate the separation of Fischer-Tropsch Synthesis (FTS) liquids from iron-based catalyst particles. Slurry-phase FTS in slurry bubble column reactor systems is the preferred mode of production since the reaction is highly exothermic. Consequently, heavy wax products must be separated from catalyst particles before being removed from the reactor system. Achieving an efficient wax product separation from iron-based catalysts is one of the most challenging technical problems associated with slurry-phase FTS. The separation problem is further compounded by catalyst particle attrition and the formation of ultra-fine iron carbide and/or carbon particles. Existing pilot-scale equipment was modified to include a filtration test apparatus. After undergoing an extensive plant shakedown period, filtration tests with cross-flow filter modules using simulant FTS wax slurry were conducted. The focus of these early tests was to find adequate mixtures of polyethylene wax to simulate FTS wax. Catalyst particle size analysis techniques were also developed. Initial analyses of the slurry and filter permeate particles will be used by the research team to design improved filter media and cleaning strategies.

  5. Nanocrystalline Ferrihydrite-Based Catalysts for Fischer-Tropsch Synthesis: Part I. Reduction and Carburization Behavior.

    PubMed

    Chun, Dong Hyun; Park, Ji Chan; Rhim, Geun Bae; Lee, Ho-Tae; Yang, Jung-Il; Jung, Heon

    2016-02-01

    Temperature-programmed reduction using H2 (H2-TPR) and CO (CO-TPR) was carried out to investigate the reduction and carburization behavior of nanocrystalline ferrihydrite-based Fe/Cu/K/SiO2 catalysts for use in Fischer-Tropsch synthesis (FTS). Unlike pure ferrihydrite, the ferrihydrite-based catalysts did not pass through the intermediate decomposition step of ferrihydrite (Fe9O2(OH)23) into hematite (a-Fe2O3) as they were reduced into magnetite (Fe3O4). This is attributed to the enhanced thermal stability induced by SiO2. For the ferrihydrite-based catalysts, the reduction of ferrihydrite into magnetite occurred in two stages because the reduction promoter, Cu, is not homogeneously distributed on the catalyst surfaces. The Cu-rich sites are likely to be reduced in the first stage, and the Cu-lean sites may be reduced in the second stage. After the ferrihydrite is reduced to magnetite, the reduction process of magnetite was similar to that for conventional hematite-based FTS catalysts: 'magnetite --> metallic iron' and 'magnetite --> wüstite (FeO) or fayalite (Fe2SiO4) --> metallic iron' in the H2 atmosphere; 'magnetite --> iron carbides' in the CO atmosphere. PMID:27433641

  6. DEVELOPMENT OF ATTRITION RESISTANT IRON-BASED FISCHER-TROPSCH CATALYSTS

    SciTech Connect

    Adeyinka A. Adeyiga

    2001-09-01

    The Fischer-Tropsch (F-T) reaction provides a way of converting coal-derived synthesis gas (CO+H{sub 2}) to liquid fuels. Since the reaction is highly exothermic, one of the major problems in control of the reaction is heat removal. Recent work has shown that the use of slurry bubble column reactors (SBCRs) can largely solve this problem. The use of iron-based catalysts is attractive not only due to their low cost and ready availability, but also due to their high water-gas shift activity which makes it possible to use these catalysts with low H{sub 2}/CO ratios. However, a serious problem with use of Fe catalysts in a SBCR is their tendency to undergo attrition. This can cause fouling/plugging of downstream filters and equipment, makes the separation of catalyst from the oil/wax product very difficult if not impossible, and results in a steady loss of catalyst from the reactor. Recently, fundamental understanding of physical attrition is being addressed by incorporating suitable binders into the catalyst recipe. This has resulted in the preparation of a spray dried Fe-based catalyst having aps of 70 mm with high attrition resistance. This Fe-based attrition resistant, active and selective catalyst gave 95% CO conversion through 125 hours of testing in a fixed-bed at 270 C, 1.48 MPa, H{sub 2}/CO=0.67 and 2.0 NL/g-cat/h with C{sub 5}{sup +} selectivity of >78% and methane selectivity of <5%. However, further development of the catalyst is needed to address the chemical attrition due to phase changes that any Fe-catalyst goes through potentially causing internal stresses within the particle and resulting in weakening, spalling or cracking. The objective of this research is to develop robust iron-based Fischer-Tropsch catalysts that have suitable activity, selectivity and stability to be used in the slurry bubble column reactor. Specifically we aim to develop to: (i) improve the performance and preparation procedure of the high activity, high attrition resistant, high

  7. Baseline design/economics for advanced Fischer-Tropsch technology. Quarterly report, April--June 1992

    SciTech Connect

    Not Available

    1992-10-01

    Effective September 26, 1991, Bechtel, with Amoco as the main subcontractor, initiated a study to develop a computer model and baseline design for advanced Fischer-Tropsch (F-T) technology for the US Department of Energy`s Pittsburgh Energy Technology Center (PETC). The objectives of the study are to: Develop a baseline design for indirect liquefaction using advanced F-T technology; prepare the capital and operating costs for the baseline design; and develop a process flow sheet simulation (PI-S) model. The baseline design, the economic analysis, and the computer model win be the major research planning tools that PETC will use to plan, guide, and evaluate its ongoing and future research and commercialization programs relating to indirect coal liquefaction. for the manufacture of synthetic liquid fuels from coal. This report is Bechtel`s third quarterly technical progress report covering the period from March 16, 1992 through June 21, 1992. This report consists of seven sections: Section 1 - introduction; Section 2 - summary; Section 3 - carbon dioxide removal tradeoff study; Section 4 - preliminary plant designs for coal preparation; Section 5 - preliminary design for syngas production; Section 6 - Task 3 - engineering design criteria; and Section 7 - project management.

  8. Correlation between Fischer-Tropsch catalytic activity and composition of catalysts.

    PubMed

    Ali, Sardar; Mohd Zabidi, Noor Asmawati; Subbarao, Duvvuri

    2011-01-01

    This paper presents the synthesis and characterization of monometallic and bimetallic cobalt and iron nanoparticles supported on alumina. The catalysts were prepared by a wet impregnation method. Samples were characterized using temperature-programmed reduction (TPR), temperature-programmed oxidation (TPO), CO-chemisorption, transmission electron microscopy (TEM), field emission scanning electron microscopy (FESEM-EDX) and N2-adsorption analysis. Fischer-Tropsch synthesis (FTS) was carried out in a fixed-bed microreactor at 543 K and 1 atm, with H2/CO = 2 v/v and space velocity, SV = 12L/g.h. The physicochemical properties and the FTS activity of the bimetallic catalysts were analyzed and compared with those of monometallic cobalt and iron catalysts at similar operating conditions.H2-TPR analysis of cobalt catalyst indicated three temperature regions at 506°C (low), 650°C (medium) and 731°C (high). The incorporation of iron up to 30% into cobalt catalysts increased the reduction, CO chemisorption and number of cobalt active sites of the catalyst while an opposite trend was observed for the iron-riched bimetallic catalysts. The CO conversion was 6.3% and 4.6%, over the monometallic cobalt and iron catalysts, respectively. Bimetallic catalysts enhanced the CO conversion. Amongst the catalysts studied, bimetallic catalyst with the composition of 70Co30Fe showed the highest CO conversion (8.1%) while exhibiting the same product selectivity as that of monometallic Co catalyst. Monometallic iron catalyst showed the lowest selectivity for C5+ hydrocarbons (1.6%). PMID:22047220

  9. Correlation between Fischer-Tropsch catalytic activity and composition of catalysts

    PubMed Central

    2011-01-01

    This paper presents the synthesis and characterization of monometallic and bimetallic cobalt and iron nanoparticles supported on alumina. The catalysts were prepared by a wet impregnation method. Samples were characterized using temperature-programmed reduction (TPR), temperature-programmed oxidation (TPO), CO-chemisorption, transmission electron microscopy (TEM), field emission scanning electron microscopy (FESEM-EDX) and N2-adsorption analysis. Fischer-Tropsch synthesis (FTS) was carried out in a fixed-bed microreactor at 543 K and 1 atm, with H2/CO = 2 v/v and space velocity, SV = 12L/g.h. The physicochemical properties and the FTS activity of the bimetallic catalysts were analyzed and compared with those of monometallic cobalt and iron catalysts at similar operating conditions. H2-TPR analysis of cobalt catalyst indicated three temperature regions at 506°C (low), 650°C (medium) and 731°C (high). The incorporation of iron up to 30% into cobalt catalysts increased the reduction, CO chemisorption and number of cobalt active sites of the catalyst while an opposite trend was observed for the iron-riched bimetallic catalysts. The CO conversion was 6.3% and 4.6%, over the monometallic cobalt and iron catalysts, respectively. Bimetallic catalysts enhanced the CO conversion. Amongst the catalysts studied, bimetallic catalyst with the composition of 70Co30Fe showed the highest CO conversion (8.1%) while exhibiting the same product selectivity as that of monometallic Co catalyst. Monometallic iron catalyst showed the lowest selectivity for C5+ hydrocarbons (1.6%). PMID:22047220

  10. Metal (Fe, Co, Ni) supported on different aluminas as Fischer-Tropsch catalyst

    NASA Astrophysics Data System (ADS)

    Dahlan, Marsih, I. Nyoman; Makertihartha, I. G. B. N.; Praserthdam, Piyasan; Panpranot, Joongjai; Ismunandar

    2015-09-01

    This research aimed to compare the physico-chemical properties of the same metal M (M = iron, cobalt, nickel) supported on aluminas with different morphology and pore size as Fischer-Tropsch catalyst. The aluminas applied as support were alumina synthesized through hydrothermal process, alumina formed by pretreatment of catapal and commercial alumina which named as Ahy, Aca, and Aco respectively. Ahy has uniform morphology of nanotubes while Aca and Aco showed non-uniform morphology of particle lumps. The particle lumps of Aca were larger than those of Aco. Ahy, Aca, and Aco respectively has average pore diameter of 2.75, 2.86 and 2.9 nm. Metals were deposited on the supports by incipient-wetness impregnation method. The catalysts were characterized by XRD, H2-TPR, and H2 chemisorption. Catalyst acitivity test for Fischer-Tropsch reaction was carried out in a micro reactor at 200 °C and 1 atm, and molar ratio of H2/CO = 2:1. The metal oxide particle size increased in the order M/Aco < M/Aca < M/Ahy. The catalysts reducibility also increased according to the order M/Aco < M/Aca < M/Ahy suggesting that the larger metal oxide particles are more reducible. The number of active site was not proportional to the reducibility because during the reduction, larger metal oxide particles were converted into larger metal particles. On the other hand, the number of active sites was inversely proportional to the particle sizes. The number of active site increased in the order M/Ahy < M/Aco < M/Aca. The catalytic activity also increased in the following order M/Ahy < M/Aco < M/Aca. The activity per active site increased according to the order M/Aca < M/Aco < M/Ahy meaning that for M/Ahy, a little increase in active site will lead to a significance increase in catalytic activity. It showed that Ahy has potential for the better support.

  11. Metal (Fe, Co, Ni) supported on different aluminas as Fischer-Tropsch catalyst

    SciTech Connect

    Dahlan; Marsih, I. Nyoman Ismunandar; Makertihartha, I. G. B. N.; Praserthdam, Piyasan; Panpranot, Joongjai

    2015-09-30

    This research aimed to compare the physico-chemical properties of the same metal M (M = iron, cobalt, nickel) supported on aluminas with different morphology and pore size as Fischer-Tropsch catalyst. The aluminas applied as support were alumina synthesized through hydrothermal process, alumina formed by pretreatment of catapal and commercial alumina which named as Ahy, Aca, and Aco respectively. Ahy has uniform morphology of nanotubes while Aca and Aco showed non-uniform morphology of particle lumps. The particle lumps of Aca were larger than those of Aco. Ahy, Aca, and Aco respectively has average pore diameter of 2.75, 2.86 and 2.9 nm. Metals were deposited on the supports by incipient-wetness impregnation method. The catalysts were characterized by XRD, H{sub 2}-TPR, and H{sub 2} chemisorption. Catalyst acitivity test for Fischer-Tropsch reaction was carried out in a micro reactor at 200 °C and 1 atm, and molar ratio of H{sub 2}/CO = 2:1. The metal oxide particle size increased in the order M/Aco < M/Aca < M/Ahy. The catalysts reducibility also increased according to the order M/Aco < M/Aca < M/Ahy suggesting that the larger metal oxide particles are more reducible. The number of active site was not proportional to the reducibility because during the reduction, larger metal oxide particles were converted into larger metal particles. On the other hand, the number of active sites was inversely proportional to the particle sizes. The number of active site increased in the order M/Ahy < M/Aco < M/Aca. The catalytic activity also increased in the following order M/Ahy < M/Aco < M/Aca. The activity per active site increased according to the order M/Aca < M/Aco < M/Ahy meaning that for M/Ahy, a little increase in active site will lead to a significance increase in catalytic activity. It showed that Ahy has potential for the better support.

  12. Iron alloy Fischer-Tropsch catalysts. V. FeCo on Y zeolite

    SciTech Connect

    Lin, T.; Schwartz, L.H.; Butt, J.B.

    1986-01-01

    A series of Fe, Co, and FeCo catalysts on Y-zeolite support, prepared both by ion exchange and impregnation, has been investigated and compared with a previously reported series supported on wide-pore SiO/sub 2/. Characterization methods were X-ray diffraction, H/sub 2/ and CO chemisorption, Moessbauer spectroscopy, and atomic absorption. The oxidation, reduction, and carburization behavior of the iron-containing catalysts were observed by Moessbauer spectroscopy. The reversibility of FeY (ion exchanged) in oxidation-reduction cycles was confirmed. The ion-exchanged catalysts (FeY, FeCoY) do not show any iron metal, or alloy or carbide phase after reduction or attempted carburization. In contrast with prior results with silica-supported Fe and FeCo, where there appear to be significant differences, Fe/HY (impregnated) and FeCo/HY appear quite similar in characterization by Moessbauer spectroscopy and in reaction behavior. A 1/1:CO/H/sub 2/ feed was used to investigate the Fischer-Tropsch reaction at 1 atm and 523 K. Some additional runs were made at a total pressure of 13.6 atm. As in prior studies it was found that the CO turnover frequency in general decreases with increasing CO conversion. A higher selectivity for higher molecular weight products is found for HY-supported catalysts, and in all cases an approximate behavior in accord with the Schultz-Anderson distribution was observed. 23 references.

  13. Influence of liquid medium on the activity of a low-alpha Fischer-Tropsch catalyst

    SciTech Connect

    Gormley, R.J.; Zarochak, M.F.; Deffenbaugh, P.W.; Rao, K.R.P.M.

    1995-12-31

    The purpose of this research was to measure activity, selectivity, and the maintenance of these properties in slurry autoclave experiments with a Fischer-Tropsch (FT) catalyst that was used in the {open_quotes}FT II{close_quotes} bubble-column test, conducted at the Alternative Fuels Development Unit (AFDU) at LaPorte, Texas during May 1994. The catalyst contained iron, copper, and potassium and was formulated to produce mainly hydrocarbons in the gasoline range with lesser production of diesel-range products and wax. The probability of chain growth was thus deliberately kept low. Principal goals of the autoclave work have been to find the true activity of this catalyst in a stirred tank reactor, unhindered by heat or mass transfer effects, and to obtain a steady conversion and selectivity over the approximately 15 days of each test. Slurry autoclave testing of the catalyst in heavier waxes also allows insight into operation of larger slurry bubble column reactors. The stability of reactor operation in these experiments, particularly at loadings exceeding 20 weight %, suggests the likely stability of operations on a larger scale.

  14. Development of improved iron Fischer-Tropsch catalysts. Final technical report: Project 6464

    SciTech Connect

    Bukur, D.B.; Ledakowicz, S.; Koranne, M.

    1994-02-28

    Despite the current worldwide oil glut, the United States will ultimately require large-scale production of liquid (transportation) fuels from coal. Slurry phase Fischer Tropsch (FT) technology, with its versatile product slate, may be expected to play a major role in production of transportation fuels via indirect coal liquefaction. Texas A&M University (TAMU) with sponsorship from the US Department of Energy, Center for Energy and Mineral Resources at TAMU, Texas Higher Education Coordinating Board, and Air Products and Chemicals, Inc., has been working on development of improved iron FT catalysts and characterization of hydrodynamic parameters in two- and three-phase bubble columns with FT derived waxes. Our previous studies have provided an improved understanding of the role of promoters (Cu and K), binders (silica) and pretreatment procedures on catalyst activity, selectivity and longevity (deactivation). The objective of the present contract was to develop improved catalysts with enhanced slurry phase activity and higher selectivity to liquid fuels and wax. This was accomplished through systematic studies of the effects of pretreatment procedures and variations in catalyst composition (promoters and binders). The major accomplishments and results in each of these two main areas of research are summarized here.

  15. Utilization of cobalt catalyst for high temperature Fischer-Tropsch synthesis in a fluidized bed reactor

    NASA Astrophysics Data System (ADS)

    Mabry, James C.

    The research determined that the improved heat transfer characteristics of a fluidized bed reactor (FBR) will allow the use of cobalt catalyst for high temperature Fischer-Tropsch synthesis (HTFT). Cobalt was loaded onto a gamma alumina support, the catalyst was characterized using TPR, BET/BJH, XRD, and PSA to track changes in the catalyst morphology. The reactor was characterized to determine the minimum fluidization velocity and the maximum velocity prior to entering lean phase fluidization with pneumatic transport of the catalyst. The highest minimum fluidization velocity was found to be about 2800 sccm, there was no maximum velocity found for the reactor setup. Once characterized, the reactor was operated at pressures of 145, 217.6, and 290.1 psig, a syngas flow rate of 4000 sccm, and at temperatures of 330 and 350 °C. The optimal conditions found in this study were 330 °C and 217 psig. At these conditions CO conversion was 83.53 % for a single pass. Methane, CO2, and light gases (C2 -- C4) selectivities were at low rates of 31.43, 5.80, and 3.48 % respectively. Alcohol selectivity at these conditions was non-existent. The olefin and wax selectivities were the lowest of the data set at 7.05 and 3.18 % respectively. Liquid transportation fuels selectivity was the highest at 56.11 %.

  16. An exploratory program for using hydrous metal oxide ion exchangers as Fischer-Tropsch catalysts

    SciTech Connect

    Lynch, A.W.; Dosch, R.G.; Sault, A.G.

    1990-01-01

    The purpose of this program is to investigate the potential of hydrous metal oxide (HMO) ion exchangers, invented at Sandia National Laboratories, as Fischer-Tropsch (F-T) catalysts. Metals known to be active in F-T synthesis (e.g. Fe, Co) were ion exchanged on hydrous metal oxide supports. Although HMO catalysts based on Zr, Nb, and Ta have been investigated in direct coal liquefaction studies, this effect focused on formulations based on the hydrous titanium oxide (HTO) system. The program has the goals of developing a catalyst with (1) high activity, (2) selectively to fuel range or other useful products, and (3) better properties for use in slurry reactors. The program has three main tasks: (1) catalyst synthesis, to develop methods for preparing catalysts having desirable F-T properties, (2) characterization, to investigate catalysts proving to have desirable properties by a variety of analytical techniques to determine correlations between activity and material properties and (3) testing to determine activity and selectivity of catalysts. This paper discussed results of activity testing of Ruhrchemie catalyst and some catalyst formulations prepared using ion exchange on hydrous titanium oxide and precipitation. For example, at 250{degree}C the Ruhrchemie catalyst converts {approximately}50% of the syngas feed to reaction products. In comparison, iron catalysts prepared by ion exchange and precipitation had conversions ranging from 20 to 50% over a temperature range of 250 to 275{degree}C of the syngas feed. In addition, results are Auger surface analysis of Ruhrchemie catalyst are presented. 6 refs., 2 figs., 2 tabs.

  17. Fischer-Tropsch synthesis in slurry reactor systems. Quarterly report, November 1, 1983-January 31, 1984

    SciTech Connect

    Satterfield, C.N.; Bartos, T.; Hanlon, R.; Matsumoto, D.; Stenger, H.

    1984-01-01

    We have now completed and partially analyzed a series of studies on the effects of the nature of the liquid present on activity and seletivity of the Fischer-Tropsch synthesis, and the effects of partial poisoning of the catalyst by H/sub 2/S or dibenzothiophene (DBT). We discovered that the presence of a small amount of DBT (97.8 mg S per g of Fe in the catalyst) cut methane formation nearly in half under a set of reaction conditions of commercial importance (263/sup 0/C, 1.48 MPa, H/sub 2//CO feed ratio = 0.69). The selectivity remained constant for at least 200 hours. This is a very important finding since reduction of methane formation is highly desirable. The catalyst activity simultaneously dropped ten-fold but it should be possible to compensate for this in other ways at least in part such as by operation at higher pressure and/or temperature. Alternately, it may develop that lesser levels of catalyst poisoning may be nearly as effective with less loss of activity. These effects are not observed with H/sub 2/S. As far as we know the effects caused by DBT are brand new and have not been observed before. We plan to exploit this lead in several ways, including optimization of DBT level and reaction conditions; study of other heterocyclic sulfur compounds, effects of activation procedures and correlation of methane selectivity with catalyst carbiding as determined by Mossbauer spectroscopy. Also of some importance was the observation that operation in the presence of an aromatic liquid (phenanthrene) increased the rate of reaction by a factor of 1.5 to 1.8, everything else being held constant.

  18. Synthesis of octane enhancers during slurry-phase Fischer-Tropsch. Quarterly technical progress report No. 7, April 1, 1992--June 30, 1992

    SciTech Connect

    Marcelin, G.

    1992-09-24

    The objective of this project is to investigate three possible routes to the formation of ethers, in particular methyl tert-butyl (MTBE), during slurry phase Fischer-Tropsch reaction. The three reaction schemes to be investigated are: addition of i-butylene during the formation of methanol and/or higher alcohols directly from CO and H{sub 2} during slurry-phase Fischer-Tropsch; addition of i-butylene to FT liquid products including alcohols in a slurry-phase reactor containing an MTBE or other acid catalyst; and addition of methanol to slurry phase FT synthesis making iso-olefins. During the seventh quarter we continued the shake down experiments for the SBCR and conducted an initial aborted run. We have also re-started experiments on Scheme 1, i.e., the addition of iso-butylene during CO hydrogenation. Using a dual bed arrangement, we have demonstrated the synthesis of MTBE from syngas and iso-butylene.

  19. Use of silicate crystallite mesoporous material as catalyst support for Fischer Tropsch reaction

    NASA Astrophysics Data System (ADS)

    Iwasaki, T.; Reinikainen, M.; Onodera, Y.; Hayashi, H.; Ebina, T.; Nagase, T.; Torii, K.; Kataja, K.; Chatterjee, A.

    1998-06-01

    Novel uniform mesoporous materials (silicate crystallite mesoporous material, SCMM) were synthesized by hydrothermal treatment of Si, Mg and/or Al containing hydroxide precipitates, along with quaternary ammonium salt, and were applied as catalyst support for Fischer-Tropsch reaction. SCMM is composed of aggregates of homogeneous layer silicate crystallites, as identified by X-ray diffraction (XRD) patterns and transmission electron microscopy (TEM) photographs which are structurally analogous to smectite clay. The mesopore of SCMM corresponds to interparticle space of disk-shaped crystallites (6-25 nm in diameter) aggregated by edge-to-face bonding. Two kinds of SCMM with variable negative charge locations were used as support materials of Co-catalysts for hydrogenation of CO. Conversion of CO was high on SCMM compared with that of silica gel. Furthermore, the main products obtained were hydrocarbons. In case of SCMM type with negative charge near the surface, olefins and branched hydrocarbons were efficiently produced in CO conversion reaction; where as another SCMM type having negative charge at the middle of crystallite platelets produced mainly normal hydrocarbons for the same reaction. This may be due to the role of the negative charge of SCMM which affects the chemical state of Co-catalyst supported on SCMM. The function of SCMM as compared to other mesoporous materials is better in terms of homogeneous and site-specific distribution of negative charge, which is further helpful in controlling the surface phenomenon as confirmed by the existence of linear CO species adsorbed on Co.

  20. Silylated Co/SBA-15 catalysts for Fischer-Tropsch synthesis

    SciTech Connect

    Jia Lihong; Jia Litao; Li Debao; Hou Bo; Wang Jungang; Sun Yuhan

    2011-03-15

    A series of silylated Co/SBA-15 catalysts were prepared via the reaction of surface Si-OH of SBA-15 with hexamethyldisilazane (HMDS) under anhydrous, vapor-phase conditions, and then characterized by FT-IR, N{sub 2} physisorption, TG, XRD, and TPR-MS. The results showed that organic modification led to a silylated SBA-15 surface composed of stable hydrophobic Si-(CH{sub 3}){sub 3} species even after calcinations and H{sub 2} reduction at 673 K. Furthermore, the hydrophobic surface strongly influenced both metal dispersion and reducibility. Compared with non-silylated Co/SBA, Co/S-SBA (impregnation after silylation) showed a high activity, due to the better cobalt reducibility on the hydrophobic support. However, S-Co/SBA (silylation after impregnation) had the lowest FT activity among all the catalysts, due to the lower cobalt reducibility along with the steric hindrance of grafted -Si(CH{sub 3}){sub 3} for the re-adsorption of {alpha}-olefins. -- Graphical abstract: The silylation of an SBA-15 before cobalt impregnation enhanced the reducibility of cobalt oxides on an SBA-15-supported cobalt catalyst and consequently increased the catalytic activity for Fischer-Tropsch synthesis. Display Omitted

  1. Manganese-oxide-supported iron Fischer-Tropsch synthesis catalysts: physical and catalytic characterization

    SciTech Connect

    Kreitman, K.M.; Baerns, M.; Butt, J.B.

    1987-06-01

    It has been claimed that catalysts containing iron and manganese are especially selective for production of low molecular weight olefins in the Fischer-Tropsch (FT) synthesis. In this study a new system, manganese-oxide-supported iron, Fe/MnO, was prepared, subjected to various calcination and reduction treatments, and then employed as a FT catalyst. Reaction studies were run with approximately 1/1: CO/H/sub 2/ feed at 515 and 540 K and 7.8 and 14.8 bar pressure. Although low conversions were employed, the synthesis rate decreased strongly with increasing conversion. Compared to conventional Fe catalysts, the Fe/MnO was more active for water-gas shift and less selective for methane and alcohols, especially at higher conversions, lower temperature, and higher pressure. Olefin selectivity was high, hydrogen chemisorption was depressed, and secondary hydrogenation was not apparent. In general it is concluded that the manganese-supported iron does promote FT selectivity for low molecular weight olefins, but at the expense of high CO/sub 2/ formation.

  2. Activation studies with a precipitated iron catalyst for Fischer-Tropsch synthesis. II. Reaction studies

    SciTech Connect

    Bukur, D.B.; Nowicki, L.; Manne, R.K.; Lang, Xiaosu

    1995-09-01

    Effects of pretreatment conditions on catalyst performance (activity, selectivity, and stability with time) during Fischer-Tropsch (FT) synthesis were studied in a fixed-bed reactor using a commercial precipitated iron catalyst (100 Fe/5 Cu/4.2K/25 SiO{sub 2} on a mass basis). The catalyst activity increased slightly with time-on-stream after hydrogen reductions, which was accompanied with conversion of metallic iron and part of iron oxides to {epsilon}{prime}-carbide ({epsilon}{prime}-Fe{sub 22}C). Initial activity of the H{sub 2}-reduced catalyst at 280{degrees}C for 8 or 24 h was markedly lower than that obtained in other tests. This is attributed to slow carburization of large oxide particles and partial poisoning of catalyst sites by migration of sulfur from the bulk to the surface of the catalyst during the reduction. Pretreatments with carbon monoxide and syngas resulted in partial conversion of Fe{sub 2}O{sub 3} to {chi}-carbide ({chi}-Fe{sub 5}C{sub 2}). During FT synthesis the CO- and the syngas-pretreated catalyst deactivated slowly with time-on-stream, due to partial conversion of {chi}-carbide to less active iron oxide phases and buildup of carbonaceous deposits which block the active sites. The hydrogen-reduced catalyst at 280{degrees}C, for 1-24h, produced more methane and gaseous hydrocarbons than the CO- or the syngas-pretreated catalyst and favored secondary reactions (1-olefin hydrogenation, isomerization, and readsorption). 41 refs., 5 figs., 2 tabs.

  3. SEPARATION OF FISCHER-TROPSCH WAX PRODUCTS FROM ULTRAFINE IRON CATALYST PARTICLES

    SciTech Connect

    James K. Neathery; Gary Jacobs; Burtron H. Davis

    2004-09-30

    In this reporting period, a fundamental filtration study was continued to investigate the separation of Fischer-Tropsch Synthesis (FTS) liquids from iron-based catalyst particles. The overall focus of the program is with slurry-phase FTS in slurry bubble column reactor systems. Hydrocarbon products must be separated from catalyst particles before being removed from the reactor system. An efficient wax product/catalyst separation system is a key factor for optimizing operating costs for iron-based slurry-phase FTS. Previous work has focused on catalyst particle attrition and the formation of ultra-fine iron carbide and/or carbon particles. With the current study, we are investigating how the filtration properties are affected by these chemical and physical changes of the catalyst slurry during activation/synthesis. The shakedown phase of the pilot-scale filtration platform was completed at the end of the last reporting period. A study of various molecular weight waxes was initiated to determine the effect of wax physical properties on the permeation rate without catalyst present. As expected, the permeation flux was inversely proportional to the nominal average molecular weight of the polyethylene wax. Even without catalyst particles present in the filtrate, the filtration membranes experience fouling during an induction period on the order of days on-line. Another long-term filtration test was initiated using a batch of iron catalyst that was previously activated with CO to form iron carbide in a separate continuous stirred tank reactor (CSTR) system. The permeation flux stabilized more rapidly than that experienced with unactivated catalyst tests.

  4. Researching Fe catalyst suitable for CO{sub 2}-containing syngas for Fischer-Tropsch synthesis

    SciTech Connect

    Wensheng Ning; Naoto Koizumi; Muneyoshi Yamada

    2009-09-15

    Fischer-Tropsch (FT) synthesis is a technology to produce liquid fuels from coal, natural gas, and biomass as an alternate to crude oil. However, the quantity of emitted CO{sub 2} from the FT process consisting of syngas preparation, FT synthesis, and product workup is one of the serious disadvantages of FT process. The conversion of CO{sub 2} into hydrocarbons is one of the promising methods to decrease CO{sub 2} emissions. Effects of promoter addition on the activity of precipitated Fe catalysts for the conversion of CO{sub 2} were studied using pure CO{sub 2} and CO{sub 2}-containing syngas feeds. The results suggested that CO{sub 2} can be activated by suitable promoter(s) for hydrocarbon synthesis at low temperature. Low K content is suitable for increasing hydrocarbon yield. The Fe catalysts promoted by equal Zn and Cu have higher CO and CO{sub 2} conversion and decreased CH{sub 4} selectivity. 36 refs., 7 figs., 3 tabs.

  5. In situ reduction study of cobalt model Fischer-Tropsch synthesis catalysts.

    PubMed

    du Plessis, Hester Esna; Forbes, Roy Peter; Barnard, Werner; Erasmus, Willem Johannes; Steuwer, Axel

    2013-07-28

    Fischer-Tropsch (FT) synthesis is an important process to manufacture hydrocarbons and oxygenated hydrocarbons from mixtures of carbon monoxide and hydrogen (syngas). The catalysis process occurs on, for example, cobalt metal surfaces at elevated temperatures and pressures. A fundamental understanding of the reduction pathway of supported cobalt oxides, and the intermediate species present during the activation, can assist in developing improved industrial supported cobalt catalysts. Hard synchrotron X-rays have the unique ability to probe atomic processes both in terms of phases present as well as the crystallographic and local structure (using the pair distribution function approach) under realistic conditions. In this manuscript we present results from measurements during in situ hydrogen activation of a model Co/alumina catalyst using in situ synchrotron X-ray powder diffraction and pair-distribution function (PDF) analysis on beam line ID31 at the ESRF in Grenoble, France. The PDF analysis showed a substantially improved understanding of the reduction of cobalt oxides, as for the first time all cobalt could be accounted for by using total scattering analysis. PMID:23752408

  6. Fischer-Tropsch slurry phase process variations to understand wax formations: Quarterly report, January 1, 1988-March 31, 1988

    SciTech Connect

    Satterfield, C.N.

    1988-01-01

    A method has been developed for caluclating the three parameters needed to characterize the carbon number distribution of products of the Fischer-Tropsch synthesis. using non-linear regression, experiemental data are fit by a modified Schulz-Flory model which has two chain growth probabilities. Excellent fit is shown for data from precipitated and fused iron catalysts. The model is used to calculate selectivity information of interest in catalyst comparison and reactor design. Advantages of this model over asymptotic regression methods are discussed in detail. 26 refs., 6 figs.

  7. Separation of Fischer-Tropsch Wax Products from Ultrafine Iron Catalyst Particles

    SciTech Connect

    James K. Neathery; Gary Jacobs; Amitava Sarkar; Burtron H. Davis

    2005-09-30

    In this reporting period, a study of ultra-fine iron catalyst filtration was initiated to study the behavior of ultra-fine particles during the separation of Fischer-Tropsch Synthesis (FTS) liquids filtration. The overall focus of the program is with slurry-phase FTS in slurry bubble column reactor systems. Hydrocarbon products must be separated from catalyst particles before being removed from the reactor system. An efficient wax product/catalyst separation system is a key factor for optimizing operating costs for iron-based slurry-phase FTS. Previous work has focused on catalyst particle attrition and the formation of ultra-fine iron carbide and/or carbon particles. With the current study, we are investigating how the filtration properties are affected by these chemical and physical changes of the catalyst slurry during activation/synthesis. The change of particle size during the slurry-phase FTS has monitored by withdrawing catalyst sample at different TOS. The measurement of dimension of the HRTEM images of samples showed a tremendous growth of the particles. Carbon rims of thickness 3-6 nm around the particles were observed. This growth in particle size was not due to carbon deposition on the catalyst. A conceptual design and operating philosophy was developed for an integrated wax filtration system for a 4 liter slurry bubble column reactor to be used in Phase II of this research program. The system will utilize a primary inertial hydroclone followed by a Pall Accusep cross-flow membrane. Provisions for cleaned permeate back-pulsing will be included to as a flux maintenance measure.

  8. SEPARATION OF FISCHER-TROPSCH WAX PRODUCTS FROM ULTRAFINE IRON CATALYST PARTICLES

    SciTech Connect

    James K. Neathery; Gary Jacobs; Burtron H. Davis

    2005-03-31

    In this reporting period, a fundamental filtration study was continued to investigate the separation of Fischer-Tropsch Synthesis (FTS) liquids from iron-based catalyst particles. The overall focus of the program is with slurry-phase FTS in slurry bubble column reactor systems. Hydrocarbon products must be separated from catalyst particles before being removed from the reactor system. An efficient wax product/catalyst separation system is a key factor for optimizing operating costs for iron-based slurry-phase FTS. Previous work has focused on catalyst particle attrition and the formation of ultra-fine iron carbide and/or carbon particles. With the current study, we are investigating how the filtration properties are affected by these chemical and physical changes of the catalyst slurry during activation/synthesis. In this reporting period, a series of crossflow filtration experiments were initiated to study the effect of olefins and oxygenates on the filtration flux and membrane performance. Iron-based FTS reactor waxes contain a significant amount of oxygenates, depending on the catalyst formulation and operating conditions. Mono-olefins and aliphatic alcohols were doped into an activated iron catalyst slurry (with Polywax) to test their influence on filtration properties. The olefins were varied from 5 to 25 wt% and oxygenates from 6 to 17 wt% to simulate a range of reactor slurries reported in the literature. The addition of an alcohol (1-dodecanol) was found to decrease the permeation rate while the olefin added (1-hexadecene) had no effect on the permeation rate. A passive flux maintenance technique was tested that can temporarily increase the permeate rate for 24 hours.

  9. SBA-15-Supported Iron Catalysts for Fischer-Tropsch Production of Diesel Fuel

    SciTech Connect

    Kim,D.; Dunn, B.; Huggins, F.; Huffman, G.; Kang, M.; Yie, J.; Eyring, E.

    2006-01-01

    Iron supported on SBA-15, a mesoporous structured silica, has been developed as a catalyst for the Fischer-Tropsch synthesis of hydrocarbons. The catalysts retain the high surface area of the support, {approx}500 m{sup 2}/g, average pore size, and pore volume. Inclusion of aluminum into the SBA-15 did not significantly alter these parameters. XRD, XAFS, and Moessbauer spectroscopies were used to characterize the catalyst before and after being subjected to the reaction conditions. Prior to reaction, the iron was distributed among {alpha}-Fe{sub 2}O{sub 3}3, ferrihydrite, and minor {gamma}-Fe{sub 2}O{sub 3}. After reaction, the iron phases detected were nonmagnetic iron oxides, iron carbide, and metallic iron. The length of the induction period typically seen with iron-based F-T catalysts was strongly dependent on the amount of aluminum present in the catalyst. With no aluminum, the induction period lasted about 25 h, whereas the induction period decreased to less than 5 h with an Al:Si mass ratio of 0.010. A further increase in aluminum content lengthened the induction period, but always remained less than that without aluminum. Catalyst activity and product selectivity were also strongly dependent on aluminum content with the maximum diesel fuel fraction, C{sub 11+}, occurring with the Al:Si ratio of 0.010 and a CO conversion of 37%. The small concentration of aluminum may serve to increase the rate of iron carbide formation, whereas higher concentrations may begin to inhibit the rate.

  10. SBA-15-supported iron catalysts for Fischer-Tropsch production of diesel fuel

    SciTech Connect

    Dae Jung Kim; Brian C. Dunn; Frank Huggins; Gerald P. Huffman; Min Kang; Jae Eui Yie; Edward M. Eyring

    2006-12-15

    Iron supported on SBA-15, a mesoporous structured silica, has been developed as a catalyst for the Fischer-Tropsch synthesis of hydrocarbons. The catalysts retain the high surface area of the support, {approximately}500 m{sup 2}/g, average pore size, and pore volume. Inclusion of aluminum into the SBA-15 did not significantly alter these parameters. XRD, XAFS, and Moessbauer spectroscopies were used to characterize the catalyst before and after being subjected to the reaction conditions. Prior to reaction, the iron was distributed among {alpha}-Fe{sub 2}O{sub 3}, ferrihydrite, and minor {gamma}Fe{sub 2}O{sub 3}. After reaction, the iron phases detected were nonmagnetic iron oxides, iron carbide, and metallic iron. The length of the induction period typically seen with iron-based F-T catalysts was strongly dependent on the amount of aluminum present in the catalyst. With no aluminum, the induction period lasted about 25 h, whereas the induction period decreased to less than 5 h with an Al:Si mass ratio of 0.010. A further increase in aluminum content lengthened the induction period, but always remained less than that without aluminum. Catalyst activity and product selectivity were also strongly dependent on aluminum content with the maximum diesel fuel fraction, C{sub 11+}, occurring with the Al:Si ratio of 0.010 and a CO conversion of 37%. The small concentration of aluminum may serve to increase the rate of iron carbide formation, whereas higher concentrations may begin to inhibit the rate. 23 refs., 6 figs., 2 tabs.

  11. SEPARATION OF FISCHER-TROPSCH WAX FROM CATALYST BY SUPERCRITICAL EXTRACTION

    SciTech Connect

    MARK C. THIES; PATRICK C. JOYCE

    1998-07-31

    The objective of this research project is to evaluate the potential of supercritical fluid (SCF) extraction for the recovery and fractionation of the wax product from the slurry bubble column (SBC) reactor of the Fischer-Tropsch (F-T) process. The wax, comprised mostly of branched and linear alkanes with a broad molecular weight distribution up to C{sub 100}, will be extracted with a hydrocarbon solvent that has a critical temperature near the operating temperature of the SBC reactor, i.e., 200-300 C. Initial work is being performed using n-hexane as the solvent. The success of the project depends on two factors. First, the supercritical solvent must be able to dissolve the F-T wax; furthermore, this must be accomplished at conditions that do not entrain the solid catalyst. Second, the extraction must be controlled so as not to favor the removal of the low molecular weight wax compounds. That is, a constant carbon-number distribution in the wax slurry must be maintained at steady-state column operation. Three major tasks are being undertaken to evaluate our proposed SCF extraction process. Task 1: Equilibrium solubility measurements for model F-T wax components in supercritical fluids at conditions representative of those in a SBC reactor. Task 2: Thermodynamic modeling of the measured VLE data for extending our results to real wax systems. Task 3: Process design studies of our proposed process. Additional details of the task structure are given.

  12. SEPARATION OF FISCHER-TROPSCH WAX FROM CATALYST BY SUPERCRITICAL EXTRACTION

    SciTech Connect

    MARK C. THIES; PATRICK C. JOYCE

    1998-10-31

    The objective of this research project is to evaluate the potential of supercritical fluid (SCF) extraction for the recovery and fractionation of the wax product from the slurry bubble column (SBC) reactor of the Fischer-Tropsch (F-T) process. The wax, comprised mostly of branched and linear alkanes with a broad molecular weight distribution up to C{sub 100}, will be extracted with a hydrocarbon solvent that has a critical temperature near the operating temperature of the SBC reactor, i.e., 200-300 C. Initial work is being performed using n-hexane as the solvent. The success of the project depends on two factors. First, the supercritical solvent must be able to dissolve the F-T wax; furthermore, this must be accomplished at conditions that do not entrain the solid catalyst. Second, the extraction must be controlled so as not to favor the removal of the low molecular weight wax compounds. That is, a constant carbon-number distribution in the wax slurry must be maintained at steady-state column operation. Three major tasks are being undertaken to evaluate our proposed SCF extraction process. Task 1: Equilibrium solubility measurements for model F-T wax components in supercritical fluids at conditions representative of those in a SBC reactor. Task 2: Thermodynamic modeling of the measured VLE data for extending our results to real wax systems. Task 3: Process design studies of our proposed process. Additional details of the task structure are given.

  13. Studying Fischer-Tropsch catalysts using transmission electron microscopy and model systems of nanoparticles on planar supports.

    SciTech Connect

    Thune, P. C.; Weststrate, C. J.; Moodley, P.; Saib, A. M.; van de Loosdrecht, J.; Miller, J. T.; Niemantsverdriet, J. W.

    2011-01-01

    Nanoparticle model systems on planar supports form a versatile platform for studying morphological and compositional changes of catalysts due to exposure to realistic reaction conditions. We review examples from our work on iron and cobalt catalysts, which can undergo significant rearrangement in the reactive environment of the Fischer-Tropsch synthesis. The use of specially designed, silicon based supports with thin film SiO{sub 2} enables the application of transmission electron microscopy, which has furnished important insight into e.g. the mechanisms of catalyst regeneration.

  14. A study on Raney iron catalyst for Fischer-Tropsch process in a slurry-phase reactor

    SciTech Connect

    Lu, Y.; Zhang, Z.; Zhou, J.

    1997-12-31

    Raney Fe, prepared by extracting Al from Fe-Al alloy, exhibits a better activity during slurry phase FT synthesis and shows distinct selectivity in low weight hydrocarbon (alkanes). Its properties, a BET surface area of at least 22m{sup 2}/g, an average pore diameter of 30nm, and similar attrition resistance as fused iron, significantly contribute to the catalyst performance such as activity, product selectivity and free separation from the waxes. This paper describes catalyst preparation and performance tests in a slurry Fischer-Tropsch synthesis. Three catalysts were compared: fused iron, precipitated iron, and Raney iron.

  15. Manganese oxide-supported iron Fischer-Tropsch synthesis catalysts: physical and catalytic characterization

    SciTech Connect

    Kreitman, K.M.

    1986-01-01

    In this study, manganese oxide-supported iron (Fe/MnO) was prepared by impregnation of powdered manganese (II) oxide with aqueous iron(III) nitrate and subjected to various calcination and reduction treatments. It was then employed as a catalyst for Fischer-Tropsch Synthesis (FTS) and its steady-state activity and selectivity behavior was observed. The FTS reaction studies were run with nearly equimolal carbon monoxide/hydrogen feed at 515 and 540 K, 7.9 and 14.8 bar pressure. Feed conversion level was kept low in order to avoid transport limitations, and was varied by adjusting space velocity. The FTS reaction rate decreased strongly with increasing conversion. Compared to unpromoted iron catalysts, the Fe/MnO catalysts were more active for the water-gas shift reaction and less selective for methane and alcohols, especially at higher conversion, lower temperature and higher pressure. The olefin selectivity was high and secondary hydrogenation was not apparent. Catalysts calcined at higher temperature exhibited stronger effects of promotion, and yielded unusually high selectivity for C/sub 2/ to C/sub 4/ hydrocarbons at low temperature and high pressure. The general conclusion is that manganese promotion or iron can promote FTS selectivity towards low molecular weight olefins, but at the expense of high carbon dioxide formation. The Fe/MnO was also physically examined using Moessbauer spectroscopy and X-ray diffraction. Iron and manganese were found to interact strongly in the calcined catalyst, though extensive phase separation occurred during reduction. The promoting effects are apparently due to partial surface coverage of iron with MnO, the extent of which is enhanced by wetter reducing conditions.

  16. Technology development for iron Fischer-Tropsch catalysis. Quarterly technical progress report No. 2, January 1, 1995--March 31, 1995

    SciTech Connect

    Davis, B.H.

    1995-05-02

    The Fischer-Tropsch synthesis has been studied over the best low-alpha catalyst developed at the CAER. A wide range of synthesis gas conversions were obtained by varying the space velocity. The experimental results show that: (1) the rate of the water gas shift reaction is lower than the rate of the Fischer-Tropsch reaction at low conversions (< 60%) whereas it closely approaches the rate of the Fischer-Tropsch synthesis at high conversions, (2) the fraction of CO converted to hydrocarbons is higher at low and intermediate conversions whereas it is smaller at high conversions, (3) the H{sub 2}/CO ratio of the product gas is equal to the H{sub 2}/CO ratio of the inlet synthesis gas at an intermediate conversion level of 67%. These findings suggest that it would be beneficial to carry out the reaction at intermediate conversions. This would result in an optimum use of CO to produce hydrocarbons rather than CO{sub 2}. High overall conversions can be obtained by either using a second reactor or recycling the product gas using a single reactor. If the intermediate conversion in a single pass is maintained at 67% there would be no need to adjust the H{sub 2}/CO ratio of the recycle stream or the feed to the second reactor as the product gas from a single pass would have the same H{sub 2}/CO ratio as the feed synthesis gas. The optimum reaction rate expression for synthesis gas conversion which has been developed for this catalyst shows that CO is strongly adsorbed on the catalyst and that the reaction products such as water and CO{sub 2} do not inhibit the reaction rate.

  17. Exploring iron-based multifunctional catalysts for Fischer-Tropsch synthesis: a review.

    PubMed

    Abelló, Sònia; Montané, Daniel

    2011-11-18

    The continuous increase in oil prices together with an increase in carbon dioxide concentration in the atmosphere has prompted an increased interest in the production of liquid fuels from non-petroleum sources to ensure the continuation of our worldwide demands while maximizing CO(2) utilization. In this sense, the Fischer-Tropsch (FT) technology provides a feasible option to render high value-added hydrocarbons. Alternative sources, such as biomass or coal, offer a real possibility to realize these purposes by making use of H(2)-deficient or CO(2)-rich syngas feeds. The management of such feeds ideally relies on the use of iron catalysts, which exhibit the unique ability to adjust the H(2)/CO molar ratio to an optimum value for hydrocarbon synthesis through the water-gas-shift reaction. Taking advantage of the emerging attention to hybrid FT-synthesis catalysts based on cobalt and their associated benefits, an overview of the current state of literature in the field of iron-based multifunctional catalysts is presented. Of particular interest is the use of zeolites in combination with a FT catalyst in a one-stage operation, herein named multifunctional, which offer key opportunities in the modification of desired product distributions and selectivity, to eventually overcome the quality limitations of the fuels prepared under intrinsic FT conditions. This review focuses on promising research activities addressing the conversion of syngas to liquid fuels mediated by iron-based multifunctional materials, highlights their preparation and properties, and discusses their implication and challenges in the area of carbon utilization through H(2)/CO(+CO(2)) mixtures. PMID:22083868

  18. Characterization of working iron Fischer-Tropsch catalysts using quantitative diffraction methods

    NASA Astrophysics Data System (ADS)

    Mansker, Linda Denise

    This study presents the results of the ex-situ characterization of working iron Fischer-Tropsch synthesis (F-TS) catalysts, reacted hundreds of hours at elevated pressures, using a new quantitative x-ray diffraction analytical methodology. Compositions, iron phase structures, and phase particle morphologies were determined and correlated with the observed reaction kinetics. Conclusions were drawn about the character of each catalyst in its most and least active state. The identity of the active phase(s) in the Fe F-TS catalyst has been vigorously debated for more than 45 years. The highly-reduced catalyst, used to convert coal-derived syngas to hydrocarbon products, is thought to form a mixture of oxides, metal, and carbides upon pretreatment and reaction. Commonly, Soxhlet extraction is used to effect catalyst-product slurry separation; however, the extraction process could be producing irreversible changes in the catalyst, contributing to the conflicting results in the literature. X-ray diffraction doesn't require analyte-matrix separation before analysis, and can detect trace phases down to 300 ppm/2 nm; thus, working catalyst slurries could be characterized as-sampled. Data were quantitatively interpreted employing first principles methods, including the Rietveld polycrystalline structure method. Pretreated catalysts and pure phases were examined experimentally and modeled to explore specific behavior under x-rays. Then, the working catalyst slurries were quantitatively characterized. Empirical quantitation factors were calculated from experimental data or single crystal parameters, then validated using the Rietveld method results. In the most active form, after pretreatment in H 2 or in CO at Pambient, well-preserved working catalysts contained significant amounts of Fe7C3 with trace alpha-Fe, once reaction had commenced at elevated pressure. Amounts of Fe3O 4 were constant and small, with carbide dpavg < 15 nm. Small amounts of Fe7C3 were found in unreacted

  19. Mechanism and kinetics of Fischer-Tropsch synthesis over supported ruthenium catalysts

    SciTech Connect

    Kellner, C.S.

    1981-06-01

    A detailed study of the kinetics of the Fischer-Tropsch synthesis of hydrocarbons, methanol, and acetaldehyde, over alumina- and silica-supported ruthenium catalysts has been carried out over a broad range of reaction conditions. Based on these results and information taken from the literature, mechanisms for the formation of normal paraffins, ..cap alpha..-olefins, methanol, and acetaldehyde have been proposed. Rate data were obtained between 448 and 548K, 1 and 10 atm, and H/sub 2//CO ratios between 1 and 3, utilizing a micro flow reactor operated at very low conversions. In addition to the studies performed with H/sub 2//CO mixtures, a series of experiments were carried out utilizing D/sub 2//CO mixtures. These studies were used to help identify rate limited steps and steps that were at equilibrium. A complementary investigation, carried out by in situ infrared spectroscopy, was performed using a Fourier Transform spectrometer. The spectra obtained were used to identify the modes of CO adsorption, the CO coverage, and the relative reactivity of different forms of adsorbed CO. It was established that CO adsorbs on alumina-supported Ru in, at least, two forms: (i) Ru-CO and (ii) OC-Ru-CO. Only the first of these forms participates in CO hydrogenation. The coverage of this species is described by a simple Langmuir isotherm. A reaction mechanism is presented for interpreting the kinetics of hydrocarbon synthesis, the olefin to paraffin ratio for each product, and the probability of chain propagation. Rate expressions based on this mechanism are reasonably consistent with the experimental data. Acetaldehyde, obtained mainly over silica-supported Ru, appears to be formed by a mechanism related to that for hydroformulation of olefins. The effect of the dispersion of Ru/Al/sub 2/O/sub 3/ catalysts on their specific activity and selectivity was also investigated. The specific activity for all products decreased rapidly with increasing dispersions.

  20. Synthesis of octane enhancer during slurry-phase Fischer-Tropsch. Quarterly technical progress report No. 4, July 1, 1991--September 30, 1991

    SciTech Connect

    Marcelin, G.

    1991-12-15

    The objective of this project is to investigate three possible routes to the formation of ethers, in particular methyl tert-butyl ether (MTBE), during slurry phase Fischer-Tropsch reaction. The three reaction schemes to be investigated are: Addition of isobutylene during the formation of methanol and/or higher alcohols directly from CO and H{sub 2} during slurry-phase Fischer-Tropsch. Addition of isobutylene to FT liquid products including alcohols in a slurry-phase reactor containing an MTBE or other acid catalyst. Addition of methanol to slurry phase FT synthesis making iso-olefins.

  1. Synthesis of octane enhancers during slurry-phase Fischer-Tropsch. Quarterly technical progress report No. 3, April 1, 1991--June 30, 1991

    SciTech Connect

    Marcelin, G.

    1991-10-15

    The objective of this project is to investigate three possible routes to the formation of ethers, in particular methyl tert-butytl ether (MTBE), during slurry phase Fischer-Tropsch reaction. The three reaction schemes to be investigated are: (1) Addition of isobutylene during the formation of methanol and/or higher alcohols directly from CO and H{sub 2} during slurry-phase Fischer-Tropsch; (2) addition of isobutylene to FT liquid products including alcohols in a slurry-phase reactor containing an MTBE or other acid catalyst; and, (3) addition of methanol to slurry phase FT synthesis making iso-olefins.

  2. Synthesis of octane enhancers during slurry-phase Fischer-Tropsch. Quarterly technical progress report No. 5, October 1, 1991--December 31, 1991

    SciTech Connect

    Marcelin, G.

    1992-06-10

    The objective of this project is to investigate three possible routes to the formation of ethers, in particular methyl tert-butyl ether (MTBE), during slurry phase Fischer-Tropsch reaction. The three reaction schemes to be investigated are: Addition of isobutylene during the formation of methanol and/or higher alcohols directly from CO and H{sub 2} during slurry-phase Fischer-Tropsch. Addition of isobutylene to FT liquid products including alcohols in a slurry-phase reactor containing an MTBE or other acid catalyst. Addition of methanol to slurry phase FT synthesis making iso-olefins.

  3. Phase transformation of iron-based catalysts for Fischer-Tropsch synthesis

    NASA Astrophysics Data System (ADS)

    Jin, Yaming

    Fischer-Tropsch (F-T) synthesis is used to convert syngas to liquid hydrocarbons using iron-based catalysts. However, the nature of the active phase and phase transformations during F-T synthesis are not well understood. In this work, the phase transformations of Fe catalysts both during F-T synthesis and controlled treatment conditions have been studied using cross-section transmission electron microscopy, x-ray diffraction and Mossbauer spectroscopy. Catalyst samples were obtained from F-T synthesis runs at medium pressure (1.48 MPa) with a H2:CO ratio of 0.7. Samples were analyzed without removal of the wax to preserve the catalyst microstructure intact and prevent oxidation due to air exposure. In all active Fe catalysts, a highly dispersed chi-carbide (Fe5C2) phase with an average particle size <10 nm was seen to be present along with larger sized particles of hexagonal Fe 7C3. On the other hand, the carbide phase whose XRD pattern resembles that obtained by the Barton and Gale was found to be associated with catalysts of low activity. All carbide particles are covered with amorphous carbonaceous layers as seen by electron energy loss spectroscopy (EELS). In a series of separate experiments, phase transformations that occur during catalyst activation at atmospheric pressure were studied. During direct CO carburization of iron oxide at 250°C, multiple nucleation sites lead to formation of smaller Fe carbide particles predominantly of the Barton-Gale carbide. However, starting from metallic Fe we obtain a chi-carbide phase without significant change in particle size. Treatment in syngas (H 2:CO = 0.7) results in less complete carburization and larger particle sizes for both the carbide and the magnetite phases. The presence of trace amounts of water vapor during reduction appears to cause formation of large faceted magnetite crystals, which are difficult to further transform to the active carbide phase. The silica support is effective at keeping the Fe phases

  4. Tailored fischer-tropsch synthesis product distribution

    DOEpatents

    Wang, Yong; Cao, Chunshe; Li, Xiaohong Shari; Elliott, Douglas C.

    2012-06-19

    Novel methods of Fischer-Tropsch synthesis are described. It has been discovered that conducting the Fischer-Tropsch synthesis over a catalyst with a catalytically active surface layer of 35 microns or less results in a liquid hydrocarbon product with a high ratio of C.sub.5-C.sub.20:C.sub.20+. Descriptions of novel Fischer-Tropsch catalysts and reactors are also provided. Novel hydrocarbon compositions with a high ratio of C.sub.5-C.sub.20:C.sub.20+ are also described.

  5. DEVELOPMENT OF ATTRITION RESISTANT IRON-BASED FISCHER-TROPSCH CATALYSTS

    SciTech Connect

    Adeyinka A. Adeyiga

    2003-12-01

    Fischer-Tropsch (FT) synthesis to convert syngas (CO + H{sub 2}) derived from natural gas or coal to liquid fuels and wax is a well-established technology. For low H{sub 2} to CO ratio syngas produced from CO{sub 2} reforming of natural gas or from gasification of coal, the use of Fe catalysts is attractive because of their high water gas shift activity in addition to their high FT activity. Fe catalysts are also attractive due to their low cost and low methane selectivity. Because of the highly exothermic nature of the FT reaction, there has been a recent move away from fixed-bed reactors toward the development of slurry bubble column reactors (SBCRs) that employ 30 to 90 {micro}m catalyst particles suspended in a waxy liquid for efficient heat removal. However, the use of Fe FT catalysts in an SBCR has been problematic due to severe catalyst attrition resulting in fines that plug the filter employed to separate the catalyst from the waxy product. Fe catalysts can undergo attrition in SBCRs not only due to vigorous movement and collisions but also due to phase changes that occur during activation and reaction. The objectives of this research were to develop a better understanding of the parameters affecting attrition of Fe F-T catalysts suitable for use in SBCRs and to incorporate this understanding into the design of novel Fe catalysts having superior attrition resistance. The catalysts were prepared by co-precipitation, followed by binder addition and spray drying at 250 C in a 1 m diameter, 2 m tall spray dryer. The binder silica content was varied from 0 to 20 wt %. The results show that use of small amounts of precipitated SiO{sub 2} alone in spray-dried Fe catalysts can result in good attrition resistance. All catalysts investigated with SiO{sub 2} wt% {le} 12 produced fines less than 10 wt% during the jet cup attrition test, making them suitable for long-term use in a slurry bubble column reactor. Thus, concentration rather than type of SiO{sub 2

  6. Development of a stable cobalt-ruthenium Fischer-Tropsch catalyst. Technical progress report No. 14, January 1, 1993--March 31, 1993

    SciTech Connect

    Frame, R.R.; Gala, H.B.

    1994-05-01

    The objective of this contract is to examine the relationship between catalytic properties and the function of cobalt Fischer-Tropsch catalysts and to apply this fundamental knowledge to the development of a stable cobalt-based catalyst with a low methane-plus-ethane selectivity for use in slurry reactors.

  7. Thermodynamic analysis of nanoparticle size effect on kinetics in Fischer-Tropsch synthesis by lanthanum promoted iron catalyst

    NASA Astrophysics Data System (ADS)

    Nakhaei Pour, Ali; Housaindokht, Mohammad Reza; Behroozsarand, Alireza; Khodagholi, Mohammad Ali

    2014-08-01

    The kinetic parameters of the Fischer-Tropsch synthesis (FTS) on iron catalyst are analyzed by size-dependent thermodynamic method. A Langmuir-Hinshelwood kinetic equation is considered for evaluation of catalytic activity of lanthanum promoted iron catalyst. A series of unsupported iron catalysts with different particle sizes were prepared via microemulsion method. The experimental results showed that catalyst activity pass from a maximum value by increasing the iron particle size. Also, data presented that iron particle size has considerable effects on adsorption parameters and FTS rates. The ratio of surface tension ( σ) to nanoparticle radius ( r) is important in FTS reaction on iron catalyst. Finally, the results showed that by increasing of iron particle size from 18 to 45 nm the activation energies of catalysts and heats of adsorption of catalysts as two main parameters of FTS reaction increased from 89 to 114 kJ/mol and from 51 to 71 kJ/mol, respectively.

  8. Study of the effects of potassium addition to supported iron catalysts in the Fischer-Tropsch reaction

    SciTech Connect

    Miller, D.G.; Moskovits, M.

    1988-10-20

    The Fischer-Tropsch activity of supported iron catalysts prepared via electrochemical techniques has been evaluated as a function of potassium addition. Catalyst pretreatment in 0.09, 0.18, and 0.27 M K/sub 2/CO/sub 3/ solutions generated potassium levels of 1.7, 2.8, and 3.9 wt %, respectively. Pretreatment in 0.18 M KOH provided a catalyst with 2.3 wt% potassium and facilitated comparison of the effects of the basicity of the pretreatment solution upon catalyst activity. A maximum in catalyst activity and CO conversion was noted upon increasing K content, followed by a sharp decline in activity at potassium levels in excess of the maximum. The hydrogenation ability of the catalyst decreased, and a shift to higher molecular weight products was observed, with increasing potassium content. The type of pretreatment solution had little effect on the catalyst activity or the product selectivity.

  9. Fischer-Tropsch synthesis in slurry-reactor systems. Quarterly report, November 1, 1981 to January 31, 1982

    SciTech Connect

    Satterfield, C.N.; Bartos, T.; Huff, G.A. Jr.; Stenger, H.

    1982-01-01

    A detailed study of mass transfer effects with a reduced fused magnetite catalyst has now been completed and is summarized in an appended paper, Mass Transfer and Product Selectivity in a Mechanically-Stirred Fischer-Tropsch Slurry Reactor, by Charles N. Satterfield and George A. Huff, Jr. Analysis of our heavier hydrocarbon products indicates that they yield a value of ..cap alpha.. = 0.93 on a Flory plot, considerably higher than the values of ..cap alpha.. of about 0.7 found with lighter products. Iron catalysts may exhibit two kinds of sites with considerably different kinetic behavior. At the request of Drs. Sapienza and Sleigeir of the Brookhaven National Laboratory, we ran a sample of their SOSS catalyst in our reactor facility at 100 psig. Activity was low, but this may have been because this particular catalyst is possibly better suited for higher pressures.

  10. Effect of Surface Modification by Chelating Agents on Fischer- Tropsch Performance of Co/SiO{sub 2} Catalysts

    SciTech Connect

    Bambal, Ashish S.; Kugler, Edwin L.; Gardner, Todd H.; Dadyburjor, Dady B.

    2013-11-14

    The silica support of a Co-based catalyst for Fischer-Tropsch (FT) synthesis was modified by the chelating agents (CAs) nitrilotriacetic acid (NTA) and ethylenediaminetetraacetic acid (EDTA). After the modification, characterization of the fresh and spent catalysts show reduced crystallite sizes, a better-dispersed Co₃O₄ phase on the calcined samples, and increased metal dispersions for the reduced samples. The CA-modified catalysts display higher CO conversions, product yields, reaction rates and rate constants. The improved FT performance of CA-modified catalysts is attributed to the formation of stable complexes with Co. The superior performance of the EDTA-modified catalyst in comparison to the NTA-modified catalyst is due to the higher affinity of the former for complex formation with Co ions.