Abstract:The reduction process of ferric iron in acid leaching solution by zinc concentrate has some problems such as low reduction efficiency, large amount of zinc concentrate and low utilization rate of ferric iron. The effects of temperature, particle size of zinc concentrate, dosage of zinc concentrate and reaction time on concentration and reduction rate of ferric iron in reducing solution were studied. The results show that reaction temperature is the main factor affecting of ferric iron reducing in solution, and the influence of zinc concentrate particle size is more obvious at low temperature reduction. Low temperature reduction requires a long time and a large amount of zinc concentrate. At 80 ℃, the particle size of zinc concentrate is less than 58 μm, the addition coefficient of zinc concentrate is more than 1.8, and the reaction time is more than 3 h, so that the concentration of ferric iron in the reducing solution is less than 0.5 g/L. The increase of temperature can shorten the reaction time and reduce the amount of zinc concentrate. At 120 ℃, the particle size of zinc concentrate is 150 μm, the addition coefficient of zinc concentrate is 1.5, and the reaction time is 1 h, the concentration of ferric iron in the reducing solution is less than 0.5 g/L. Using pressure process to increase reduction temperature can effectively improve the utilization rate of zinc concentrate and the reduction rate of ferric iron, reduce the amount of reduction residue, which is conducive to the subsequent treatment of reduction residue.