Process for preparing silica-alumina

摘要: A process for preparing silica-alumina compositions comprises mixing a first aqueous solution containing an aluminum salt (preferably KAl(SO4)2) and ammonium (NH4)2 SO4) with second alkali metal silicate Na2 SiO3), wherein the mol ratio of to is in range from about 2:1 20:1, concentration chosen so as afford coprecipitation hydrogel at pH 3-6). The thus coprecipitated can be separated mixture two solutions, optionally washed, calcined prepare acidic suitable cracking catalyst material.