Document Type : Research Paper
Department of Engineering, University of Kashan, 8731753153 Kashan, Iran
Our recent studies revealed that the ground sulphide minerals in contact with water generate H2O2 but its effect on the oxidation of pulp components and hence in deteriorating the concentrate grade and recovery in flotation has not been explored yet. The use of Na2S reductant at the grinding stage is thought to control the deleterious effects of H2O2 in the pulp liquid. Therefore, the effect of Na2S addition during grinding stage on the formation of H2O2 and its influence on sulphide complex ore flotation was investigated. The results showed that the presence of Na2S increases the formation of H2O2 but decreases the dissolved oxygen. An increase in Na2S dosage in grinding, the Pb grade and recovery in Cu-Pb concentrate is decreased while pyrite is depressed marginally better. These changes in flotation response of sulphides have been discussed and explained with the formation of H2O2 quantitatively.