Extractive separation of uranium and zirconium sulfates by amines
DOE Office of Scientific and Technical Information (OSTI.GOV)
Schroetterova, D.; Nekovar, P.; Mrnka, M.
1992-04-01
This paper describes an amine extraction process for zirconium and uranium separation. The behaviour of an extraction system containing uranium (VI) sulfate, zirconium (IV) sulfate, 0.2 and 0.5 M sulfuric acid (as the original aqueous phase), tertiary amine tri-n-lauryl- amine or primary amine Primene JMT in benzene (as the original organic phase) is discussed on the basis of equilibrium data. The measured dependences show that the degree of extraction of zirconium at the sulfuric acid concentration of 0.5 M and above is only slightly affected by a presence of uranium in solution. From this surprising behaviour it follows that zirconiummore » may be employed for the displacement of uranium from the organic phase. This effect is more pronounced with the primary amine Primene JMT than with TLA. 29 refs., 4 figs., 1 tab.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Timmins, T.H.; Mason, E.A.
1963-04-01
An investigation of the solvent extraction characteristics of nitric acid and the nitrato complexes of nitrosylruthenium was conducted, using alkyl amines as extractants. The alkyl amines used were a primary amine Primene JMT, a tertiary amine trilaurylamine (TLA), and a quaternary amine Aliquat 336. The organic phase concentrations of HNO/sub 3/ resulting during extraction by alkyl amines were found to correlate well on the basis of the undissociated aqueous HNO/ sub 3/ activity for both salted (NaNO/sub 3/) and unsalted aqueous phases. The distribution ratios for Ru extraction showed better correlation on this basis than on the basis of aqueousmore » phase nitrate and nitric acid. The order of decreasing Ru extraction at low HNO/sub 3/ concentration (2N) was found to be Aliquat 336, TLA, and Primene JMT. At high HNO/sub 3/ concentration (9N). Primene JMT had the highest Ru extractability. Hapid dilution experiments were utilized to determine the number and aqueous phase concentrations of the extractable species of Ru, and the amine partition coefficients for the species. It was found that two Ru species are extractable, and the more extractable species is present in the aqueous phase at lower concentration than the less extractable species. The mole fractions of both species were found to increase with increasing HNO/sub 3/ concentration. The TLA partition coefficients for the extractable species were found to decrease with increasing HNO/sub 3/ concentration. The quaternary amine, Aliquat 336, was found to have partition coefficients an order of magnitude greater than the tertiary amine, TLA. Equations for the mole fractions and TLA partition coefficients in the region of HNO/sub 3/ concentration investigated were developed. (auth)« less
Acid extraction by supported liquid membranes containing basic carriers
DOE Office of Scientific and Technical Information (OSTI.GOV)
Danesi, P.R.; Cianetti, C.; Horwitz, E.P.
1983-01-01
The extraction of HNO/sub 3/ (nitric acid) from aqueous solutions by permeation through a number of supported liquid membranes containing basic carriers dissolved in diethylbenzene has been studied. The results have shown that the best permeations are obtained with long chain aliphatic amines (TLA, Primene JM-T) followed by TOPO (trioctylphosphine oxide) and then by other monofunctional and bifunctional organophosphorous basic carriers. The influence of an aliphatic diluent on the permeability of HNO/sub 3/ through a supported liquid membrane containing TLA as carrier was also investigated. In this case the permeability to HNO/sub 3/ decreases as a result of the lowermore » diffusion coefficient of the acid-carrier complex in the more vicous aliphatic solvent. 4 figures.« less
Brykala, M; Deptula, A; Rogowski, M; Lada, W; Olczak, T; Wawszczak, D; Smolinski, T; Wojtowicz, P; Modolo, G
A new method for synthesis of uranium oxide microspheres (diameter <100 μm) has been developed. It is a variant of our patented Complex Sol-Gel Process, which has been used to synthesize high-quality powders of a wide variety of complex oxides. Starting uranyl-nitrate-ascorbate sols were prepared by addition of ascorbic acid to uranyl nitrate hexahydrate solution and alkalizing by aqueous ammonium hydroxide and then emulsified in 2-ethylhexanol-1 containing 1v/o SPAN-80. Drops of emulsion were firstly gelled by extraction of water by the solvent. Destruction of the microspheres during thermal treatment, owing to highly reactive components in the gels, requires modification of the gelation step by Double Extraction Process-simultaneously extraction of water and nitrates using Primene JMT, which completely eliminates these problem. Final step was calcination in air of obtained microspheres of gels to triuranium octaoxide.
Li, L.; Drake, R. R.; Clement, S.; Brown, R. M.
1993-01-01
Using differential product entrapment and photolabeling under specifying conditions, we identifIed a 37-kD polypeptide as the best candidate among the UDP-glucose-binding polypeptides for the catalytic subunit of cotton (Gossypium hirsutum) cellulose synthase. This polypeptide is enriched by entrapment under conditions favoring [beta]-1,4-glucan synthesis, and it is magnesium dependent and sensitive to unlabeled UDP-glucose. A 52-kD polypeptide was identified as the most likely candidate for the catalytic subunit of [beta]-1,3-glucan synthase because this polypeptide is the most abundant protein in the entrapment fraction obtained under conditions favoring [beta]-1,3-glucan synthesis, is coincident with [beta]-1,3-glucan synthase activity, and is calcium dependent. The possible involvement of other polypeptides in the synthesis of [beta]-1,3-glucan is discussed. PMID:12231766
RADIATION STABILITY OF ORGANIC LIQUIDS. Semi-Annual Report No. 4 for July 1 to December 31, 1958
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wagner, R.M.; Towle, L.H.
1959-01-01
0 @ 4 2 7 1 8 3 7 1 7 6 TBP from 0 to 100 were irradiated with electrons to 300 to 400 whr/liter. The G(total acid) values obtained indicated that, from 0 to 60 wt, % TBP, the acid produc tion rate is proportional to wt, % TBP; above 60 wt, % TBP the acid production rate is lower. Normalized total acid G values, obtained by partition of the dose on a basis of wt, % TBP, ranged from 2.31 to 3.52. Seven TBP-Amsco solutions, ranging from 5 to 60 wt. % TBP, and samples of puremore » TBP and pure dibutyl phenylphosphorate (DBPP) were irradiated to 400 whr/liter, Five compositions of TBP, DBPP, Amsco, and tetralin were irradiated to 200 whr/liter. The amount of radiationinduced unsataration was measured for each of the above samples. The data indicated that unsaturation varied inversely with wt. % TBP. The DBPP exerted a small protective effect, as did tetralin, in reducing radiation damage to the Amsco. Diethyl carbonate, irradiated to 392 whr/liter, had a G(gas) value of 4.86, a--G (target destruction) value of 5.50, and a --G /sub M/(polymer) value of 2.80. Diethyl carbonate, after irradiation, extracts U better than virgin material and strips equally as well. The irradiated diethyl carbonate exhibited no difference from virgin material in emulsification tendency. Dibutyl phenylphosphorate-Amsco systems, at dose levels of either 200 or 400 whr/liter, showed that acid production is about proportioral to wt. % DBPP. Studies of DBPP-Amsco-tetralin systems at 200 whr/ liter indicated that tetralin is more acceptable than decalin for enhancing the solubility of the DBPP-uranium complex in Amsco, thus suppressing third-phase phenomena. Tetralin also reduced acid production from DBPP under irradiation. Tributyl phosphate, dibutyl phosphoric acid, and di-(2- ethylhexyl) phosphoric acid were irradiated in the pure state to 300 whr/liter. The G(gas) values were 1.9, 3.3, and 3.1, respectively, and the G(total acid) values were 2.3, 2.1, and 1.2. The--G values for target converted to polymer were 0.22 for the DBP, and 0.32 for the D2EHP. Tri-n-octyl phosphine oxide was irradiated in the pure state to 400 whr/liter. The G(gas) value of 1.82 was comparable to a value of 1.45 found previously at 2040 whr/1iter. Values of --G/ sub M/ for target and polymer were approximately double the values previously found at 2040 whr/ liter. Amines, including tri-lauryl amine, n-benzyl heptadecyl amine, tri-iso-octyl amine, Primene JM-T, and tri-oetyl-decyl-t-amine (Alamine) were irradiated to either 200- or 400-whr/liter doses. The Primene produced the lowest --G (polymer) value, (1.50) and the Alamine produced the highest -- G/sub M/(total target destroyed) value (3.49). An Alamine-tridecanol- Amsconitric acid system yielded the lowest G(gas) value (1.89) while the corresponding tri-lauryl amine system produced the highest (3.12). The most extensive emulsification occurred with the 0.5M tri-lauryl amtne-Amscotridecanol system while the n-benzyl heptadecyl amine system exhtbited the lowest emulsification tendency, The most efficient U extractant system observed was the Alamine-Amsco-tridecanol-nitric acid composition, at the 0.5M-Alamine level. A comparison was made of the quantity and composition of material removed from irradiated TBP-Amsco by various scrubbing media. A single scrub with 2M NaOH appears four times more efftcient than does a single scrub with satarated CaOH in removing acidic radiolysis products. The emulsification tendency of the scrubbed organic appears to increase with the quantity of acidic radiolysis products removed. Radiolysis products other than those of acidic natare (polymer) are apparently not removed by the scrubbing media investigated in this study. An ir« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Linsley, B.K.; Dunbar, R.B.; Mucciarone, D.A.
1994-05-15
Seasonal movements of the Intertropical Convergence Zone (ITCZ) control precipitation patterns and cloud cover throughout the tropics. In this study the authors have reconstructed seasonal and interannual variability of the eastern Pacific ITCZ from 1984 to 1707 using subseasonal {delta}{sup 18}O analyses on a massive coral from Secas Island (7{degrees}59{prime}N, 82{degrees}3{prime}W) in the Gulf of Chiriqui, Panama. The land area that drains into the Gulf of Chiriqui has served to amplify the rainfall effect on nearshore surface waters and coral {delta}{sup 18}O{sub ppt} composition. During the protracted wet season in Panama, the {delta}{sup 18}O of precipitation ({delta}{sup 18}O{sub ppt}) ismore » reduced on average by 10{per_thousand} and sea surface salinity (SSS) along the western coast is reduced up to 11{per_thousand}. Calibration of the coral {delta}{sup 18}O{sub ppt} from Secas Island against instrumental sea surface temperature (SST), SSS, precipitation and {delta}{sup 18}O{sub ppt} data indicate that seasonal rainfall induced variations in seawater {delta}{sup 18}O are responsible for {approximately}80% of the annual {delta}{sup 18}O variance. The regularity of the reconstructed seasonal ITCZ cycle indicates that over the length of the record the zone of maximum rainfall in the eastern Pacific has always expanded north to at least Panama in every northern hemisphere summer. Significant interannual and interdecadal {delta}{sup 18}O oscillations occur at average periods near 9, 3-7 (ENSO band), 17 and 33 years (listed in order of decreasing variance). As the Gulf of Chiriqui coral {delta}{sup 18}O time series is the first paleoclimatic record of past variations in the ITCZ, other seasonal-resolution reconstructions of the past behavior of the ITCZ are required to test whether the interannual and long-term variability observed in the eastern Pacific ITCZ is more than regional in scale. 79 refs., 13 figs., 2 tabs.« less