Variation of stability constants of thorium and uranium oxalate complexes with ionic strength

Abstract

The extraction of Th(IV) and UO!+ by a solution of TTA and HDEHP, respectively in toluene has been used to obtain stability constants of their oxalate complexes at 298 Κ in 1, 3, 5, 7 and 9 Μ ionic strength (NaC104) solutions. The complexes formed were the MOx, MHOx, MOx2 and M(HOx)2 (M = Th, U02) species. The values were analyzed by the Specific Interaction Theory and agreed to / < 3 Μ but required an additional term for fitting at / > 3 M.