Sustainable Thermochemical Extraction of Amorphous Silica From Biowaste

Abstract The objective is to utilize zero wastage rice hull material which contains major component silica in amorphous and used as reinforcement material for various applications. Burning of hull in controlled condition after removal of metal ions leads to white silica of high purity. An economical method for extraction of amorphous natural silica by thermochemical treatment (pyrolysis process) is performed. The pyrolyzed biomass at four different temperatures is observed for treated and untreated rice hull. Calcination of rice hull at 600ºc in muffle furnace turns into white amorphous natural silica. In this research, inorganic acid HCl is used to retrieve silica from rice hull. Synthesized Silica is characterized by X-ray diffraction analysis, which indicates that the silica is amorphous form, it displayed a strong broad peak at 22.32º and 21.52˚ (2q). The FT-IR data was revealed the existence of peaks at 4000 cm-1& 400 cm-1 showing the siloxane & silanol groups were present, Fluorescence Spectrophotometer, SEM and EDS.