Mutual separation method of platinum group elements

摘要

PROBLEM TO BE SOLVED: To provide a method capable of improving the recovery rate of platinum (Pt) in a method for mutually separating a platinum group element from a platinum group element-containing substance containing an impurity element. The present invention is a method for mutually separating a platinum group element from a platinum group element-containing substance containing an impurity element, in which the platinum group element-containing substance is suspended in a hydrochloric acid solution and an oxidizing agent is added for leaching. Then, the leaching step S1 to obtain the leaching product containing the platinum group element, the solvent extraction step S2 (S2A, S2B) in which the obtained leaching product is subjected to the solvent extraction treatment, and the extraction residual liquid obtained by the solvent extraction treatment. Includes a cake-making step S3 of adding potassium chloride to 20 g / L or more in the extraction residual liquid to produce a precipitate. [Selection diagram] Fig. 1