China Petroleum & Chemical Corporation
Method of producing a highly-pure aluminum hydroxide

Abstract:

A method of producing a highly-pure aluminum hydroxide, comprising the following steps: (1) reacting alcohol with metal aluminum to produce aluminum alkoxide, then hydrolyzing the aluminum alkoxide with water to produce an aluminum hydroxide slurry and an alcohol, filtering the aluminum hydroxide slurry, washing a resulting filter cake with water to remove the alcohol trapped therein, and drying the filter cake after the water washing to produce an aluminum hydroxide powder, (2) sending the alcohol-containing water produced in step (1) to an alcohol extraction unit for separating water and alcohol through extraction, and sending the separated water back to step (1) for recycling, (3) dehydrating the hydrous alcohol produced by hydrolyzing the aluminum alkoxide in step (1) before using it as the raw materials for reacting metal aluminum with alcohol to produce aluminum alkoxide in step (1). The method can improve the recovery of alcohol, reduce the production cost of a highly-pure aluminum hydroxide, improve the purity of aluminum oxide and achieve a zero discharge of sewage by recycling water.