Boron Removal from Prepared Rice Hulls Ash Metallurgical-Grade Silicon via Solvent Refining Process

Metallurgical grade siliconSilicon (MG-Si) derived from an agricultural wasteWastes rice husk (RH) via metallothermicMetallothermic reduction of pulverized Mg and SiO2 mixtureMixture at ratio 1:1 g was treated and purified by hydrometallurgical purificationPurification process. A low-cost siliconSilicon with high purity was produced by solvent refiningSolvent refining process. In this work, silica of 98.03% has been prepared from rice hulls annealed at 700 °C for 6 h. Furthermore, the silica value was boosted by improved purificationPurification processes to yield 99.51% of silica. The X-ray fluorescence (XRF) showed that several metallic trace impurities were significantly reduced beyond its detection limit. The final process underwent centrifuge of solvent refined siliconSilicon with tin as a selected gettering metal. The X-ray mappingMapping and energy-dispersive X-ray spectroscopy (EDS) quantitative analysis showed that B was eliminated. The XRF of final siliconSilicon powder showed purity > 98.5%.