PRODUCTION OF THE STABLE-COMPOSITION SILICA-CARBON MATERIAL FROM RICE HULLS

The conducted research was aimed at studying the composition and structure of the silica-carbon material produced during the rice hulls pyrolysis, and control of the hydrocarbons composition stabilization process. In the course of the research, the mechanism of hydrocarbon phases' transformation during the rice hulls thermal decomposition was determined. It was demonstrated that the temperature was the principal factor having influence on transformation of the hydrocarbon phases. It was found that in the temperature range of 300-500°С three hydrocarbon phases were present in silica-carbon: the stable phase, unstable polynaphthenic phase and resinous phase. At temperatures of 600-700 °С the polynaphthenic phase partially transformed into the carbon phase and resinous hydrocarbons volatilized. The technology was developed to produce silica-carbon with the stable-composition hydrocarbons that met the requirements as to the fillers for carbon structural materials and elastomers as well as the charge material for production of high-purity silicon.