Poly-generation of activated carbon and silica from rice husk charcoal

In order to effectively utilize the solid product of gasification electricity generation, the optimum reaction conditions of the poly-generation technology for production of activated carbon and silica extraction from the rice husk charcoal were optimized by single-factor experiment. The results showed that the optimal conditions were as follows: the liquid-solid ratio of K2CO3 solution(mass fraction of 20%) to rice husk charcoal was 15:1(mL/g), and the mixture was melted at 100℃ for 3.5 h; The carbonization temperature and activation temperature for rice husk activated carbon was 450℃ and 850℃, respectively, and activation time was 2 h. The aging temperature and aging time for silica was 3℃ and 3h respectively. Under these conditions, the yield of activated carbon was 39.34%, the iodine adsorption value was 978.35 mg/g, and the methylene blue adsorption value was 12 mL/0.1 g. The yield of SiO2 was 25.77% and its whiteness was 89.91%. The experiment indicated that the quality of rice husk activated carbon and silica product prepared in this process both reached to the national standards. The research can provide a practical way for the high efficiency, pollution-free and resource utilization of rice husk charcoal.