EXTRACTION OF MO(VI) FROM NITRIC-ACID SOLUTIONS BY DIPHENYL[DIBUTYLCARBAMOYLMETHYL]PHOSPHINE OXIDE

Extraction of Mo(VI) and Am(III) from nitric acid solutions by solutions of diphenyl[dibutylcarbamoylmethyl]phosphine oxide in fluoropol has been studied as a function of the phase contact time and concentrations of nitric acid, reagent, and molybdenum. Two different mechanisms of extraction of macroamounts of Mo(VI) are observed, depending on the acid concentration: from weakly acidic solutions the polymeric forms of molybdenum are predominantly extracted, whereas from strongly acidic solutions the monomeric nitrate complexes are extracted; equilibrium is attained within 9 h and 3 min, respectively. The possibility has been demonstrated of americium(III) separation from molybdenum(VI) during reextraction with solutions of acetohydroxamic acid in 1 M nitric acid.