Patent ID: 7390358
Filing Date: 2008-06-24
Classification: B01J

Abstract:
1. A method for preparing a modified kaolin clay, comprising the steps of: providing a kaolin clay material having a starting ratio of silica to alumina; mixing said kaolin clay material with acid so as to form a substantially homogenous paste; calcining the paste so as to provide a calcined acid-treated clay material, wherein said calcining step is carried out at a temperature of between about 250 and about 350° C.; mixing said calcined acid-treated clay material in water so as to form a suspension; precipitating aluminum from said suspension so as to produce a reduced aluminum suspension, wherein said precipitation step is sequentially carried out at a pH of 4, 7, and 11; obtaining a modified clay material from said reduced aluminum suspension, wherein said modified clay material has a final ratio of silica to alumina which is higher than said starting ratio.