Production of metallurgical-grade silicon from egyptian quartz

Abstract

(-4-Metallurgical-grade silicon (MG-Si) was successfully produced by carbothermic reduction-smelting of Egyptian quartz using a mixture of carbonaceous materials in a locally made semi-pilot submerged arc furnace. The effects of different technical parameters such as the carbon to silica ratio, smelting time, power input, and weight ratio of carbon sources were investigated. The MG-Si product was characterized by X-ray diffraction (XRD), X-ray fluorescence (XRF), and scanning electron microscopy (SEM). A maximum silicon recovery of about 75% at a product purity of about 97% was achieved under the optimum experimental conditions of 80 minutes’ smelting time, 48 kW power input, and a carbon/silica ratio of 0.39.