Study on Leaching of Gallium and Scandium from a Gibbsite-Type Bauxite

Abstract

This is an article in the field of metallurgical engineering. There are high contents of gallium and scandium in bauxite, which has great recovery value. The study on the leaching behavior of gallium and scandium in bauxite leaching process is of great significance for the extraction and utilization of gallium and scandium. The leaching behavior of gallium and scandium from gibbsite bauxite was studied. The results showed that gallium was easy to be leached into the solution. Increasing the temperature, prolonging the reaction time and increasing the mass concentration of sodium hydroxide were conducive to the leaching of gallium. The leaching rate of gallium could reach over 73%, and adding calcium oxide reduced the leaching rate of gallium. The gallium content in the solution was accumulated during the cyclic digestion process. After 3 cycles, the gallium concentration in the decomposition mother liquor reached 24.2 mg/L. Both red mud and decomposition mother liquor had high gallium content and had recycling value. Scandium was not easy to be leached. After digestion, 97.4% of scandium was enriched in red mud. The object of scandium recovery and extraction was mainly red mud.

Keywords

• metallurgical engineering
• alumina
• gallium
• scandium
• leaching
• red mud