China Nonferrous Metallurgy

Using organic cobalt remover in zinc hydrometallurgy has become a trend, but the mechanism of its influence on the zinc electrowinning process is still unclear, and there is a phenomenon of affecting zinc electrowinning and “burning plates”. In response to this problem, this article studied the influence of organic cobalt removal reagents on the zinc electrowinning process by directly adding sodium dimethyldithiocarbamate to the prepared zinc electrolyte and the zinc electrolyte prepared with a new solution removed cobalt by sodium dimethyldithiocarbamate, and the following conclusions were drawn. The use of organic sodium dimethyldithiocarbamate to remove cobalt will cause the loss of Zn²⁺ in the new solution, resulting in an imbalance of the acid zinc ratio during the zinc electrowinning process, which will increase the electricity consumption of the zinc electrowinning; a certain concentration of sodium dimethyldithiocarbamate in the electrolyte will increase the viscosity of the solution, and a small amount of sodium dimethyldithiocarbamate can reduce the surface energy and viscosity of the solution; the adhesion of sodium dimethyldithiocarbamate on the cathode will cause hydrogen to precipitate strongly on the cathode, causing “burning” phenomenon; the ultraviolet spec-trophotometry method for the determination of thiram is a new method discovered in this experiment, and the determination method is simple, easy to operate, the standard material easy to obtain.