Solvent extraction of rhenium from molybdenum in alkaline solution

The technology of selective extraction of rhenium from alkaline solutions containing rhenium and molybdenum by solvent extraction using a mixture of tributyl phosphate and triotylamine as extractant has been investigated, complete separation of rhenium from alkaline solutions containing rhenium and molybdenum was possible after repeated extraction and repeated stripping. The results show that the mixture of 20% triotylamine and 30% tributyl phosphate diluted kerosene oil is selective extractant of rhenium with respect to molybdenum. It extracted molybdenum with extraction efficiency of 1.7%, while rhenium was extracted with efficiency of 96.8%, and separation coefficient βRe/Mo is relatively good (1.7 × 103). The optimum extraction conditions have been determined experimentally as: “20% triotylamine and 30% tributyl phosphate, pH of the feed solution (9.0), room temperature, phase ratio (1:1)”, Stripping of rhenium to aqueous phase was efficient when 18% ammonia liquor were applied, the rhenium stripping efficiencies in the examined conditions were about 99.3% under conditions of O:A ratio of 1:1 for 10 min at 40 °C.