Kyanite ore processing by carbochlorination

• Carbochlorination of kyanite can be used for metallurgical alumina production.
• Mullitization co-process increases the carbochlorination extent of kyanite.
• The dependence of carbochlorination rate obtained: Al2O3 < SiO2 < kyanite < mullite.

Kyanite, mullite and model kyanite ore carbochlorination processing was investigated in laboratory experiments and thermodynamics' calculations. The extraction of 94% alumina and silica takes place as a result of calcined kyanite carbochlorination at 1300 °C for 90 min at normal pressure. Kyanite processing into AlCl3 + SiCl4 gas mixture is proposed for high purity alumina, nanodispersed silica and solar-grade silicon production.