Assessment of synthesis methods of SiO2 produced from rice husk and its main physicochemical characteristics

Extraction of silica from rice husk is an emerging trend in the current research field. Large amount of rice husk (RH) are treated as waste and disposed of at the landfill site. These waste materials can also cause fire, which may lead to severe environmental pollutions. The airborne particles produced from dust may induce respiratory disease to human beings. The burning of rice husk results in the formation of rice husk ash (RHA) with major SiO2 content with 10 to 20% of carbon and organic components depending on the burning conditions, the furnace type, the rice variety, the climate and the geographical area. Moreover, the commonly used silica precursor like tetraethoxysilane is more expensive, and hence rice husk ash(RHA) and other waste sources having silica are used as an alternative. Acid leaching of the rice husk can carried out to remove soluble elemental impurities and hence it increases the purity of the silica content. The organic compounds in rice husk and other waste materials can be decomposed under burning conditions. In recent years, environmental demand and sustainable development have become increasingly important. It is important to study and utilize RH biowaste, and convert RHs into valued materials. This is the focus of this research. This paper article will be methods of synthesis SiO2 from rice husk and its physical-chemical characteristics