Silicon carbide formation from pretreated rice husks

The differences in nature of organic matter in raw rice husks (RRH) and coked rice husks (CRH), and their effect on silicon carbide synthesis have been studied by means of infrared spectroscopy and X-ray diffractometry, so that the benefit of RH structure is fully exploited. Both RRH and CRH can be used as precursors for SiC synthesis, although different reaction kinetics and thus different control parameters are required. It is proposed that kinetics of silicon carbide synthesis from rice husks can be divided into 3 stages: organic decomposition, transformation of silica and condensed organic/graphite, and silicon carbide formation. (C) 2003 Kluwer Academic Publishers.