PROCESS FOR EXTRACTING COBALT WITH LOW NICKEL CONTENT FROM AQUEOUS SOLUTIONS OF COBALT AND NICKEL

摘要

The invention relates to a process for separating cobalt from magnesium and nickel by liquid-liquid extraction. The invention is essentially characterised in that magnesium-containing aqueous solution, which contains cobalt and nickel, is brought into contact with an organic solution, which contains dialkylphosphoric acid, monoalkyl alkylphosphonate or monoalkyl alkyl phosphinate, under conditions at which the partition coefficient (distribution coefficient) of the cobalt is at least 1.5 times greater than the partition coefficient of the magnesium and at the same time at least 30 times greater than the partition coefficient of the nickel, the cobalt-magnesium ratio of the aqueous solution before or during the extraction being set to the range 0.2-2. IMAGE