Liquid-liquid extraction of uranium(VI) with enanthic, caprylic, pelargonic acids and their binary mixtures in benzene

Abstract

The extraction of uranium(VI) into benzene containing enanthic, caprylic and pelargonic acid (HR)(2) has been carried out. Basing on slope analysis, the extracted species are found to be UO(2)R(2)(HR)(2). The extraction efficiencies of the extractants enanthic (heptanoic), caprylic (octanoic) and pelargonic (nonanoic) acids in the extraction of U(VI) have been compared. The influence of various parameters such as equilibrium pH, extractant concentration on the extraction was found to be in an increasing order with the increase in both the factors. The optimum shaking time was found to be 10 sees for all the three acid extractants. Stripping with various mineral acids, namely aq. HCl, HNO3, H2SO4 and HClO4, was carried out at different concentrations, where aq. HCl, HNO3 and HClO4 gave almost the same trend but with aq. H2SO4 the extraction was quantitative at lower concentration which decreases with increase in acid strength. Synergism with the binary mixture of the extractants was studied and found to be in increasing order up to 0.1 M of the binary mixture, after which it decreases.