Separation of molybdenum and iron by Tri-n-butyl phospate extraction

The extraction of Mo and Fe from sulfuric and nitric acid solutions with tributylphosphate has been studied. It has been found that Mo is extracted from weakly acid solutions of both acids with high distribution coefficients. Practically, Mo cannot be extracted from concentrated HNO3 and H2SO4 solutions. Conditions for effective separation of Mo and Fe from weak H2SO4 solutions have been determined. The optimum pH value in the case of selective extraction of Mo with TBP is 0.65 to 0.75. The regularities of extractive separation of Mo from Fe from HNO3 and H2SO4 solutions in the presence of H2O2 have been examined. It is shown that Mo and Fe can be effectively separated by extraction from HNO3 solutions at pH = 0.5 and from 3 to 4 n H2SO4 solutions, as well as from a mixture of these acids. It is likewise shown that Mo is fully reextracted from the organic phase with a 10% NH4OH + 5% NH4NO3 solution