Effect of Temperature on the Extraction of Plutonium(VI) by Tri n-Amyl Phosphate

Abstract

Plutonium(VI) / Solvent extraction / Enthalpy of extraction / Tri n-amyl phosphate SummaryThe effect of temperature on the extraction of plutoniuni(VI) by tri n-amyl phosphate (TAP) from nitric acid media has been studied and the results are reported here. The enthalpies for the extraction derived from the distribution ratios are found to be exothermic, like the enthalpies of extraction of Pu(VI) by tri nbutyl phosphate (TBP). Attempts have been raade to evaluate the free energy change, the entropy change and the equilibrium constant, for the extraction reaction of this ion from the enthalpy of extraction. Results of studies on the extraction of nitric acid by TAP are also reported.

Effect of structure of N,N dialkyl amides on the extraction of U(VI) and Th(IV): a thermodynamic study

“…It was observed that the extraction of U(VI) and Th(IV) decreased with increase in temperature, suggesting the exothermic nature of the extraction equilibria. Similar observations have been reported for the extraction of U and Pu with solvating organophos- phorus extractants like tri-n-butyl phosphate (TBP), trin-amyl phosphate (TAP), sulphoxides like di-2-ethylhexyl sulphoxide (DEHSO) and amides like dihexyl hexanamide (DHHA) [19][20][21][22][23][24]. Due to very low D Th values (≤ 10 −3 ) at 3 M HNO 3 , the extraction experiments could not be carried out in the case of D2EHIBA and D2EHPVA.…”