The Chemistry of Protactinium. VIII. : Synergistic Effect of Di-isobutyl Carbinol on the Pa(V)-TTA-Benzene Solvent Extraction System

For the purpose of understanding the behavior of protactinium in a perchloric acid solution toward TTA-benzene extraction, the effect of di-isobutyl carbinol (DIBC) on the extraction was studied. A marked synergism was observed. As a result of a detailed investigation of such things as the effects of the TTA concentration, of the DIBC concentration, and of the acidity, the unified mechanism of TTA-benzene and TTA-DIBC-benzene extraction is considered to be a series of successive reactions, (1) through (4), with an increase in the DIBC concentration:PaOm(OH)n5−2m−n+4HT=Pa(OH)2T3(HT)+(m+n−2)H2O+(5−2m−n)H+ Pa(OH)2T3(HT)→PaOT3(HT) (slow, irreversible) (1)PaOm(OH)n5−2m−n+4HT=Pa(OH)2T3(HT)B+(m+n−2)H2O+(5−2m−n)H+ Pa(OH)2T3(HT)B→PaOT3(HT)B (slow, irreversible) (2)PaOm(OH)n2−2m−n+3HT+B=Pa(OH)2T3B+(m+n−2)H2O+(5−2m−n)H+ Pa(OH)2T3B→PaOT3B (slow, irreversible) (3)PaOm(OH)n5−2m−n+3HT+2B=Pa(OH)2T3B2+(m+n−2)H2O+(5−2m−n)H+ Pa(OH)2T3B2→PaOT3B2 (slow, irreversible) (4)The slow, irreversible reaction in each step indicates t...