X-rayfluorescencespectrometry(XRF),X-raypowderdiffractometry(XRD)andscanningelectronmicroscopy(SEM)wereusedtocharacterizethechemicalcomposition,phaseconstituentandmicrostructureofthecoalgasificationslag.Sialonpowdersweresynthesizedbycarbothermalreductionandnitridationusingthecoalgasificationslagasrawmaterials.Theexperimentalresultsshowedthatglassandamorphouscarbonwerethemainphases,quartzandcalciteasminorcrystallinephaseswerealsopresentedinporouscoalgasificationslag.MainconstituentsofcoalgasificationslagwereSiO2,Al2O3,CaOandresidualcarbon.SialonpowderwithCa-α-Sialonasmaincrystallinephasecanbesynthesizedwhencoalgasificationslagpowderswerereducedandnitridedat1500℃for9husingnitrogenflowof500ml/min.ThecoalgasificationslagisavaluableandeconomicstartingmaterialforpreparingSialonpowders.
