The uranium(VI) extraction mechanism of D2EHPA-TOPO from a wet process phosphoric acid

This paper reports the results of an investigation into the solvent extraction of uranium from technical grade phosphoric acid using industrially available extractants as D2EHPA and TOPO diluted in technical grade kerosene. Preliminary tests showed that, the effect of different parameters such as uranium oxidation stage, temperature and the molar ratio of D2EHPA/TOPO on the uranium recovery was in good agreement with those of previous investigations. However, a detailed investigation into the effect of phosphoric acid concentration, organic concentration and acid/organic phase ratios suggested that the mechanism of D2EHPA/TOPO synergism was rather complex and it presented a different character depending on the acid concentration.