An Improved Process for the Preparation of High-Quality Bio-silica Microparticles from Rice Husk Ash

摘要

An improved method for the production of silica from a low cost, abundant biomass rice husk using a sodium carbonate extraction followed by 2-acrylamido-2-methylpropane sulfonic acid (AMPS) treatment is reported. The effect of mass fraction of base, reaction time and temperature, AMPS mass fraction, and equilibration time on the silica yield, as well as the regeneration and reusability of AMPS have been investigated. Materials were characterized by X-ray diffraction, N_2 adsorption, FT-IR and scanning electron microscopy. The yield of SiO_2 particles is 99% and the specific surface area is 425 m~2/g with average particle size of 100 nm. Silica produced with this method shows better properties compare with those produced by conventional methods.