Effects of gas atmosphere on reduction of quartz and its reaction with silicon carbide for silicon production

Wider use of solar energy is impeded by high cost of solar-grade silicon used in photovoltaics. Carbothermal synthesis of silicon carbide (SiC) followed by further reacting with quartz is a novel and economical approach for production of solar-grade silicon. The aim of the project was to investigate carbothermal reduction of quartz to SiC and production of silicon from quartz and SiC in different gas atmosphere, and establish reaction mechanism. The concentrations of CO, CO2 and CH4 in the off gas during reaction were measured online using an infrared gas analyzer. The samples after reduction were characterized by XRD, LECO analyser, SEM and TEM. The major findings of this project are as follows: