An increase in extraction of nonferrous metals from ferrous cakes of the copper-nickel production

Ferrous cake of copper-nickel production—koagel or ferrogel—transforms into the lyosol state under the effect of flocculants, which is accompanied by the release of coprecipitated nonferrous metals. The effective flocculant—iron(III) chloride—is established, which can be prepared immediately from the ferrous cake upon its dissolution in hydrochloric acid. The optimal molar ratio of iron(III) in the flocculant and ferrous cake is determined. A material balance of peptization allowing for flocculant preparation is proposed. It is shown that the use of the flocculant makes it possible to increase the extraction of nonferrous metals from the cake by 60–80% on average during the first repulping compared with the solution of sulfuric acid and water applied according to the acting technology.