Investigations into complex processing of zinc cakes

Abstract

Investigations are carried out into the processing of zinc cakes with the purpose of transferring zinc, copper, and iron from ferrites into a solution and of concentrating noble metals in the lead-containing silicate product. Zinc cakes are subjected to sulfatization by oleum followed by leaching with a concentrated H2SO4 solution. With the use of a planned multifactor experiment according to the Box plan, the effect of the H2SO4 content in the leaching solution on the cake leaching process, its duration, and temperature has been studied. Due to this, the models of the dependence of the listed factors on the extraction of Zn, Fe, and Cu into the solution have been obtained. The possibility of an almost complete extraction of these metals into the solution is demonstrated. The following leaching conditions are suggested as optimal: H2SO4 concentration of 8.33 g/l in the leaching and washing solutions, leaching time of 2 h, and leaching temperature of 75°C.