Sample records for dephenolization
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Strategies for dephenolization of raw olive mill wastewater by means of Pleurotus ostreatus.
Olivieri, Giuseppe; Russo, Maria Elena; Giardina, Paola; Marzocchella, Antonio; Sannia, Giovanni; Salatino, Piero
2012-05-01
The reduction of polyphenols content in olive mill wastewater (OMW) is a major issue in olive oil manufacturing. Although researchers have pointed out the potential of white-rot fungus in dephenolizing OMW, the results available in the literature mainly concern pretreated (sterilized) OMW. This paper deals with the reduction of polyphenols content in untreated OMW by means of a white-rot fungus, Pleurotus ostreatus. Dephenolization was performed both in an airlift bioreactor and in aerated flasks. The process was carried out under controlled non-sterile conditions, with different operating configurations (batch, continuous, biomass recycling) representative of potential industrial operations. Total organic carbon, polyphenols concentration, phenol oxidase activity, dissolved oxygen concentration, oxygen consumption rate, and pH were measured during every run. Tests were carried out with or without added nutrients (potato starch and potato dextrose) and laccases inducers (i.e., CuSO₄). OMW endogenous microorganisms were competing with P. ostreatus for oxygen during simultaneous fermentation. Dephenolization of raw OMW by P. ostreatus under single batch was as large as 70%. Dephenolization was still extensive even when biomass was recycled up to six times. OMW pre-aeration had to be provided under continuous operation to avoid oxygen consumption by endogenous microorganisms that might spoil the process. The role of laccases in the dephenolization process has been discussed. Dephenolization under batch conditions with biomass recycling and added nutrients proved to be the most effective configuration for OMW polyphenols reduction in industrial plants (42-68% for five cycles).
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Bozkoyunlu, Gaye; Takaç, Serpil
2014-01-01
Olive mill wastewater (OMW) with total phenol (TP) concentration range of 300-1200 mg/L was treated with alginate-immobilized Rhodotorula glutinis cells in batch system. The effects of pellet properties (diameter, alginate concentration and cell loading (CL)) and operational parameters (initial TP concentration, agitation rate and reusability of pellets) on dephenolization of OMW were studied. Up to 87% dephenolization was obtained after 120 h biodegradations. The utilization number of pellets increased with the addition of calcium ions into the biodegradation medium. The overall effectiveness factors calculated for different conditions showed that diffusional limitations arising from pellet size and pellet composition could be neglected. Mass transfer limitations appeared to be more effective at high substrate concentrations and low agitation rates. The parameters of logistic model for growth kinetics of R. glutinis in OMW were estimated at different initial phenol concentrations of OMW by curve-fitting of experimental data with the model.
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Catalytic coal liquefaction with treated solvent and SRC recycle
Garg, Diwakar; Givens, Edwin N.; Schweighardt, Frank K.
1986-01-01
A process for the solvent refining of coal to distillable, pentane soluble products using a dephenolated and denitrogenated recycle solvent and a recycled, pentane-insoluble, solvent-refined coal material, which process provides enhanced oil-make in the conversion of coal.
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Catalytic coal liquefaction with treated solvent and SRC recycle
Garg, D.; Givens, E.N.; Schweighardt, F.K.
1986-12-09
A process is described for the solvent refining of coal to distillable, pentane soluble products using a dephenolated and denitrogenated recycle solvent and a recycled, pentane-insoluble, solvent-refined coal material, which process provides enhanced oil-make in the conversion of coal. 2 figs.
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Processing of Janina coal at 600 atm. to gasoline and middle oil. Second progress report (in German)
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hupfer, H.; Leonhardt
1944-03-13
The experiments described here were run in a 10-liter hydrogenation oven which was fitted with an outlet for desanding the reaction mixture to keep down the formation of caviar deposits in the oven. The experiments proceeded very well, and the Janina coal proved to be one that was very well suited to hydrogenation because of its relatively low carbon content. The coal gave high yields of products (0.35 kg/liter/hour), low losses to gases (18.6%), and low levels of asphalt formation. Although the fact needed further confirmation in full-scale operations, it seemed that the Janina coal did not require as highmore » a temperature from the preheater as did other coals in order to initiate the reaction (about 400/sup 0/C vs. about 425/sup 0/C). One of the disadvantages of the Janina coal was the fact that its rather large yield of liquid-phase gasoline had lower octane number than that from some other coals (Heinitz coal, for example - about 71 vs. 74). The gasoline contained 33% paraffins, 35% naphthenes, 23% aromatics, and 9% unsaturated compounds. The gasoline contained 11% phenol, whereas the middle oil contained 20.5% phenols. The aniline point of the various dephenolized fractions of gasoline varied from 18.2 to 36.0/sup 0/, whereas the aniline point of the various dephenolized fractions of middle oil varied from -24.5 to -14.0/sup 0/. The solidifying point of the heavy oil was 9/sup 0/C. 7 tables.« less
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Process for solvent refining of coal using a denitrogenated and dephenolated solvent
Garg, Diwakar; Givens, Edwin N.; Schweighardt, Frank K.
1984-01-01
A process is disclosed for the solvent refining of non-anthracitic coal at elevated temperatures and pressure in a hydrogen atmosphere using a hydrocarbon solvent which before being recycled in the solvent refining process is subjected to chemical treatment to extract substantially all nitrogenous and phenolic constituents from the solvent so as to improve the conversion of coal and the production of oil in the solvent refining process. The solvent refining process can be either thermal or catalytic. The extraction of nitrogenous compounds can be performed by acid contact such as hydrogen chloride or fluoride treatment, while phenolic extraction can be performed by caustic contact or contact with a mixture of silica and alumina.
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NASA Astrophysics Data System (ADS)
Zhang, Yue-Hua; Li, Jing; Wang, Xue; Xue, Chun-Mei
2018-03-01
As phenol as the sole carbon source, the activated sludge was screened and acclimated to obtain the superior phenol-degrading bacteria capable of degrading high phenol concentration. The mixed bacteria completely degraded 1700mg/L phenol in 15h, to 102.9mg/L; the degradation rate reached 96.9%. After isolation and purification, four different single strains were obtained, and the genus of each strain was preliminarily identified. At the same time, the effects of initial phenol concentration, bacteria dosage, temperature and pH on the degradation of COD and phenol by phenol-degrading bacteria were also investigated. The mixed bacteria de-phenol effect is better than the four isolates were isolated.
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Monti, Matilde; Scoma, Alberto; Martinez, Gonzalo; Bertin, Lorenzo; Fava, Fabio
2015-05-25
Among agro-wastes, olive mill wastewater (OMW) truly qualifies as a high impact organic residue due to its biochemical-rich composition and high annual production. In the present investigation, dephenolized OMW (OMWdeph) was employed as the feedstock for a biotechnological two-stage anaerobic process dedicated to the production of biohydrogen and volatile fatty acids (VFAs), respectively. To this end, two identically configured packed-bed biofilm reactors were operated sequentially. In the first, the hydraulic retention time was set to 1 day, whereas in the second it was equal to 5 days. The rationale was to decouple the hydrolysis of the organic macronutrients held by the OMWdeph, so as to quantitatively generate a biogas enriched in H2 (first stage aim), for the acidogenesis of the residual components left after hydrolysis, to then produce a highly concentrated mixture of VFAs (second stage aim). Results showed that the generation of H2 and VFAs was effectively split, with carbohydrates and lipids, respectively, being the main substrates of the two processes. About 250 ml H2 L(-1) day(-1) was produced, corresponding to a yield of 0.36 mol mol(-1) of consumed carbohydrates (expressed as glucose equivalents). The overall concentration of VFAs in the acidogenic process was 13.80 g COD L(-1), so that 2.76 g COD L(-1) day(-1) was obtained. Second generation biorefineries use a selected fraction of an organic waste to conduct a microbiologically-driven pathway towards the generation of one target molecule. With the proposed approach, a greater value of the waste was attained, since the multi-purpose two-stage process did not entail competition for substrates between the first and the second steps. Copyright © 2014 Elsevier B.V. All rights reserved.