Abstract:Taking zinc neutral leaching residue as the research object, experimental study was carried out on the reduction leaching and SO2 reduction leaching of zinc sulfide concentrate, and the characteristics of the two processes were analyzed. With the continuous dissolution of zinc ferrite in the leaching process, a large amount of Fe3+ enters the solution, which leads to the increase of solution potential and inhibits the decomposition of zinc ferrite. Reductive leaching can effectively alleviate the effect of high potential on the decomposition of zinc ferrite in solution and improve the metal leaching rate. The two processes were analyzed from four aspects: leaching behavior of elements, composition of reductive leaching solution, composition of reductive leaching residue and treatment of reductive leaching residue. The results show that the two processes can effectively reduce Fe3+ to Fe2+ in solution, promote the dissolution of zinc ferrite, improve the leaching rate of valuable metals, and facilitate the separation of zinc and iron in subsequent processes. It can achieve harmless treatment and resource utilization of medium leaching residue.