Acid Leaching Performance of Gibbsite-type Bauxite with High Iron Content

Abstract

High-iron bauxite with low A/S ratio cannot be extracted economically by Bayer process. Taking a low-grade gibbsite ore abroad as the research object, the acid leaching performance of gibbsite was studied by using hydrochloric acid as leaching medium. The effects of ore particle size, liquid-solid ratio, time and temperature on leaching efficiency were investigated. The results show that temperature has a significant effect on the leaching effect of aluminum. When the particle size of ore is 55 μm, the ratio of liquid to solid is 100:7, the temperature is 105℃, and the time is 120 min, the leaching rate of aluminum and iron are both higher than 95%, and they are effectively leached. It is consistent with the characterization of leaching residue. The kinetics of the acid leaching process of the high iron gibbsite ore shows that the acid leaching process of iron and aluminum is controlled by internal diffusion.

Keywords

• acid leaching
• bauxite
• alumina