Autoclave leaching of boehmite-kaolinite bauxites by hydrochloric acid

The process of the autoclave leaching of boehmite-kaolinite bauxite of Severoonezhsk deposits by hydrochloric acid is researched. The effect of temperature, process time, and concentration of hydrochloric acid necessary for the aluminum transition into solution are investigated. The rate constants and apparent activation energy of the process are determined. The mechanism of bauxite dissolution in hydrochloric acid is proposed. It is shown that the kaolinite dissolution is the limiting stage of the process. The results obtained make it possible to synthesize a new generation of mixed coagulants based on aluminum hydroxychloride and iron.