Production and Characterization of Silica from Rice Husk: An Updated Review

Rice is regarded as one of the most valuable sources which is consumed by almost fifty percent of the world’s population. Rice husk ash is a by-product substance obtained from the rice husk by thermal and chemical treatment. The non-crystalline nature of silica content in rice husk, which is converted to crystalline silica such as quartz, tridymite, and cristobalite on thermal treatment. It has been an important material which impacts not only enhances the betterment of industrialization but also protects the environment from pollution. The produced silica was characterized by various analyses such as Fourier transform infrared spectroscopy (FTIR), X-ray diffraction analysis (XRD), Scanning electron microscope (SEM), Transmission electron microscope (TEM), and Thermal analysis. This review is given attention to integrating and investigating processing, properties, characterization, reactivity, and application of rice husk (RH) and rice husk silica (RHS).