Abstract:To address relatively few research issues related to separation of cobalt and manganese from high-concentration cobalt sulfate feed solution, process to extract and separate Ca2+, Co2+ and Mn2+ from industrial high-concentration cobalt sulfate solution with mixed extraction system formed by P204 and TBP was studied. Effects of extraction equilibrium pH value, volume fraction of TBP, extraction phase ratio, and degree of saponification of organic phase on extraction rate of Ca2+, Co2+ and Mn2+ were investigated. Ca2+, Co2+ and Mn2+ were separated via washing organic phase. The results show that extraction rate of Ca2+, Co2+ and Mn2+ is 88.1%, 69.8% and 19.3%, respectively under the conditions including 25% P204+10% TBP as extractant, 65% kerosene as diluent, equilibrium pH value of water phase of 3.7, saponification rate of 45%, and O/A=1︰2. With 30 g/L manganese sulfate solution as washing solution, and under washing conditions including equilibrium pH value of water phase of 3.5, O/A=20︰1, and washing series of 4, concentration of Mn2+ in loaded organic phase is 7.14 g/L, concentration of Ca2+ and Co2+ is only 0.05 g/L and 0.14 g/L. This process effectively realizes separation of cobalt, manganese and calcium in high-concentration cobalt sulfate solution.