Behavior of noble metals in the process of pyrometallurgical processing of sulfide copper-nickel ores

Abstract

In sulfide copper-nickel ores, as is known, there are always noble metals-silver, gold, and platinoids. Platinoids are of special importance - their value in some cases may be equal to copper and nickel. This makes it necessary to include special operations related to the extraction of noble metals in the processing of copper and nickel ores. Practice has shown that noble metals in the pyrometallurgical process follow the metal-containing product, i.e. in the course of copper-nickel ore processing they are sequentially concentrated in matte and high-grade matte. It is believed that the separation smelting process also separates noble metals into two groups: 1) gold and silver mainly follow copper; 2) platinoids follow nickel. Thus, already at the first stage of pyrometallurgical processing - in ore smelting - noble metals are selectively concentrated in the sulfide phase (matte) preferably before the silicate phase (slag). The nature of this phenomenon has not been accurately established until now. In the present work an attempt is made to reveal the reason for the concentration of noble metals in sulfides during ore smelting of copper-nickel ores and in the subsequent stages of pyrometallurgical processing - during conversion of copper-nickel matte and separation smelting.