Electrochemical effects in flotation of a Turkish complex sulphide ore

Abstract

There are many reported studies of selective flotation based on control of redox potential (Eh). Most of the studies show that flotation of chalcopyrite, pyrite, sphalerite and galena with xanthate collector show a strong dependency on Eh, although there are some conflicting views about the potentials where the maximum mineral recoveries occur and the beneficial effects of Eh for selective flotation. In this paper, controlling the pulp potential and its effect on roughing flotation for Cu is reported for laboratory flotation of a well characterised complex sulphide ore from Turkey. Several ways of controlling the pulp potential such as pH variation, addition of oxidising or reducing agents, aeration, oxygenation and nitrogenation are discussed. The results show that there is a relationship between pulp potential and Cu flotation as pH of the pulp is changed whilst larger variation in Cu recoveries and grades were possible by changing operating conditions such as the point of the pH adjustment, flotation gas and using combinations of collectors. A general relationship between flotation performance and pulp potential could not be found.