PRODUCTION OF ALUMINUM-BASED CHEMICAL AND SILICA-BASED CHEMICAL FROM COAL ASH

摘要

PROBLEM TO BE SOLVED: To provide a technique to produce aluminum sulfate from Al2O3, and water glass (sodium silicate) and white carbon from SiO2 in coal ash. SOLUTION: Sulfuric acid is added to coal ash essentially consisting of SiO2 and Al2O3, and the mixture is heated. A chemical agent of aluminum sulfate is produced from the filtrate of the reaction. Or, a chemical agent of water glass (sodium silicate) or white carbon is produced from the residue of filtration. The aluminum sulfate, water glass or white carbon obtained from the reaction is preferably used for paper making. The sulfuric acid is preferably the waste sulfuric acid from the producing device of chlorine dioxide used as a bleaching agent for pulp.