| Abstract Scope |
Rice husk, an agricultural waste product, could yield valuable silica under controlled temperature and time. Its low production cost makes it most viable for preparing metallurgical grade silicon (MG-Si).
In this work, high purity MG-Si ~ 98% has been prepared from rice husk ash (RHA) by extraction. The RHA silica was leached using HNO3 and HCl solutions. Leached RHA was filtered, washed, dried and calcined at 1000oC for 5 h. Further purification was achieved by thoroughly mixing the silica with magnesium powder at a ratio of 1.0g SiO2 to 0.8g Mg, annealed at 1100oC to form magnesium silicide. The material produced was characterized by XRF, XRD and FTIR spectroscopy. Elemental analysis using XRF found percentage of silicon in the material to be 98%, major impurities are Mg (0.96%), Ca (0.08%), Fe (0.2%), K (0.26%), and Al (0.39%). Further analysis using Raman spectroscopy show polycrystalline Si line at 516.6 cm−1. |