Hydrometallurgical purification of metallurgical grade silicon

The effects of the particle size of ground metallurgical grade silicon (MG‐Si), the sort of acids, and the type of stirring on the purified efficiency of MG‐Si were investigated. It was found that a particle size less than 0.1 mm was most effective for acid leaching; the extraction yield of impurities was increased by 9% with HF leaching compared with HCl leaching and HNO 3 leaching, and increased by 7% with ultrasonic stirring compared with mechanical stirring. The principle of hydrometallurgical purification of metallurgical grade silicon under ultrasonic fields was also discussed.