Copper-refining process

Abstract

Abstract In an integrated process, copper-bearing materials are leached with dilute sulfuric acid and the dilute pregnant leach solution is reacted with ferrous scrap to produce cement copper precipitate containing copper metal, ferrous impurities and normally refractory metal impurities. The raw cement copper is preliminarily treated to separate portions of the ferrous impurities and is then melted and reacted with chlorine under a metal halide flux cover. The chlorine selectively reacts with the refractory metals and the ferrous impurities, forming chlorides which are dissolved by the halide flux to produce a slag containing entrained copper metal, copper chloride and the impurity metal chlorides. After separation of the substantially pure copper metal remaining in the melt, the readily friable slag is cooled to solidification and crushed. Entrained copper metal particles are removed from the crushed slag by screening and recycled to the chlorine refining step. The remainder of the slag is leached with water to dissolve the copper chloride and the pregnant copper chloride solution is recycled to the cementation step to recover the copper values.

Inventors

• 👤 Frank D Chew

Bibliographic Details