REMOVAL OF IRON OXIDE COMPONENT

PURPOSE:To remove an iron oxide component and to obtain a crystal having excellent hardness and (thermal) impact resistance and useful for an antiwearing material etc., by heating and melting an amorphous slag obtained through partial oxidation of coal and crystallizing the molten slag. CONSTITUTION:An amorphous slag which is produced in partially oxidizing coal by the Texaco process etc. for formation of a synthetic gas is pulverized into a powder having a fineness of 1,000cm /g or more in terms of Blaine specific surface area. If necessary, a carbonaceous component such as a coke powder is added thereto for an uncombustible carbon contained in an amount of 0.5-4wt% in such an amount as will provide a C/Fe (amount, in terms of Fe, of iron oxide component contained in the slag) atomic ratio of 0.2-6. The slag is heated and molten at 1,500 deg.C or higher for about 2hr and crystallized to obtain a molten slag having an Fe2O3 content of 1.5% or less.