Spectrophotometric study of uranium(VI) chelate formation with beta-diketones and tributyl phosphate in aqueous, nona(oxyethylene) dodecyl ether solution.
The distribution ratio of uranium(VI) with 2-thenoyltrifluoroacetone, 2-furoyltrifluoroacetone and benzoyltrifluoroacetone in the presence and absence of tributyl phosphate between micellar and bulk phases in nona(oxyethylene) dodecyl ether solution was measured spectrophotometrically as a function of hydrogen-ion concentration. The thermodynamic constants for these reactions were evaluated from the variation of the equilibrium constants as a function of temperature. The entropy change contributes to the synergistic reaction.
Synergistic extraction of uranyl complexes with TTA-TBPO mixtures into various solvents
Abstract The synergistic effect in extraction of uranyl complexes with a mixture of thenoyltrifluoroacetone (TTA) and tributyl phosphine oxide (TBPO) has been studied by using the uranium-237 tracer. The synergistic complex in this system has been found to be UO 2 A 2 · S ( A : TTA anion; S : TBPO), whereas no higher adducts such as UO 2 A 2 · mS ( m > 1) have been observed. The extraction constants ( K eχ , S ) and the adduct formation constants ( K S ) have been determined in twelve organic solvents. These equilibrium constants much depend on the kind of solvent used, e.g. log K S = 7·00 in methylene chloride and 9·18 in cyclohexane. The sequence of the log K S values in different solvents is similar to that for TBP adduct of UO 2 A 2 . The regularity in the adduct formation constants has been discussed.
Comparative odor control performance of activated carbon and permanganated alumina
Abstract Activated carbon and permanganated alumina were compared with regard to their effectiveness in reducing the odor levels of air streams containing olefin. ester, aldehyde, ketone, amine, sulfide, mercaptan, decomposed crustacean shell vapor, or state tobacco vapor. In all cases, the odor-reducing effect of the activated carbon was much faster than that of the permanganated alumina. For the odors of stale tobacco and decomposed crustacean shells, the permanganated alumina, after it was reduced to MnO2, gave evidence of prolonged partial odor reduction, probably by serving as a catalyst for oxidation by air.