Removal of Iron from Metallurgical Grade Silicon with Pressure Leaching

Abstract

In this paper, removal of iron from metallurgical grade silicon with pressure leaching is carried out. We investigated the factors such as the concentration of hydrochloric, particle size of raw material ground, temperature, pressure and reaction time, which influenced on the removal of iron. The results show that the optimum operating conditions for pressure leaching in hydrochloride are: acid concentration 4 mol/L, diameter for raw material less than 50 μm, leaching temperature 160 0C，leaching pressure 2.0 MPa, leaching time 2.0 h. The content of iron residual in MG-Si powder was reduced to about 200 ppmw. The removal efficiency of iron is up to 90.90 %.

Chemical Cracking Effect of Aqua Regia on the Purification of Metallurgical-Grade Silicon

“…However, their main disadvantages are the high production cost and consequent environmentally hazardous substances, which hinder the widespread use of silicon solar cells. , In this context, the metallurgical process for producing SOG-Si from metallurgical-grade silicon (MG-Si) has attracted substantial interest because of its low cost and level of energy consumption . The process is comprised of acid leaching, oxidization refining, vacuum treatment, directional solidification, etc.…”

“…1,2 In this context, the metallurgical process for producing SOG-Si from metallurgicalgrade silicon (MG-Si) has attracted substantial interest because of its low cost and level of energy consumption. 3 The process is comprised of acid leaching, 4 oxidization refining, 5 vacuum treatment, 6 directional solidification, 7 etc.…”

Effect of oxidizing agents on the hydrometallurgical purification of metallurgical grade silicon

“…and Ma et al (2009) have studied the ultrasonic acid leaching of MGSi, and found that leaching under ultrasonic conditions is more effective than under simple magnetic stirring. Xie et al (2011) have successfully obtained more than 90% extraction of iron by pressure leaching of MGSi with hydrochloric acid. The kinetics of pressure leaching for the purification of MGSi with hydrochloric acid have also been investigated by Yu et al (2011).…”

Kinetics of iron removal from metallurgical grade silicon with pressure leaching

“…More recently, we determined the optimum condition of iron removal in MG-Si via pressure leaching [13]. In the previous literature, however, we did not report the kinetic evaluation and the fundamental kinetics of pressure leaching of MG-Si with hydrochloric acid.…”