Preparation of Silica from Rice Husks

摘要: Preliminary leaching of rice husks with a solution hydrochloric acid before their combustion at 600°C is shown to be required obtain relatively pure silica (∼99.5%) high specific surface area (∼260 m2/g) that maintained even after heating 800°C. Transmission electron microscopy observations indicate this material has homogeneous size distribution nanometric particles. However, if the HCl performed on white ashes obtained by 600°C, an amorphous same purity also obtained, but its decreases 1 m2/g. This behavior due strong interaction between and potassium contained in husks, which leads dramatic decrease K+ cations are not removed prior heat treatment 600°C. finding better understanding effect morphology silica.