Separation of Tungsten from Phosphorus-Containing Molybdate Solution Using Solvent Extraction with Primary Amine N1923

a solvent extraction process for separation of tungsten from phosphorus-containing molybdate solution was developed using acidified primary amine n1923 as extractant. most tungsten combines with phosphorus to form phosphorus-containing polymeric ions over a proper ph range, while the dominant form of molybdenum is still monomeric ions (moo42−). the former can be preferentially extracted by acidified n1923. the initial ph, extractant concentration, 2-octanol concentration, and temperature were optimized. by employing an initial ph of 7.5, 15% by volume n1923, 5% by volume 2-octanol, t = 20°c, and o:a ratio of 1:1, 97.0% tungsten was extracted in a single stage, while limiting molybdenum coextraction to 12.5%. the concentration of wo3 in the raffinate was reduced to 0.28 g/l after two-stage continuous countercurrent extraction.