The Preparation of Well-Dispersed White Carbon Black (hydrated silica) From Coal Gangue Via a Carbonation Method

Qualified white carbon black (hydrated silica) was prepared from the coal gangue through a series of process including calcination, acid leaching, melting with sodium carbonate and eventually synthesis through a carbonization method. This research work specially focused on the study of the carbonization reaction and ethanol has been choosed as addition agent in order to produce well-dispersed hydrated silica. The quantity of the addition agent ethanol, the ratio of Si to Na and the concentration of sodium silicate have been studied as the main factors. The as－prepared hydrated silica product was analyzed by Ft-IR, XRD, XRF, SEM and laser particle size analyzer. The results indicate that a more dispersed white carbon black product could be synthesized when the ratio of Si to Na is set at 1.5 and the concentration of the sodium silicate is set at 10 'Be°. Meanwhile, the concentration of ethanol in the whole system is set at 1 mol／L.