METHOD FOR TREATING RESIDUE AFTER EXTRACTING PHTHALIC ANHYDRIDE

摘要

PROBLEM TO BE SOLVED: To provide a method for treating residue after extracting phthalic anhydride with which the residue after extracting phthalic anhydride as an industrial waste can be treated at a low cost without bringing about an environmental problem. SOLUTION: The residue after extracting phthalic anhydride generated in a distillation-refining process of the low purity phthalic anhydride is used as a part of a refining agent when a desulfurizing refining to molten iron alloy is performed. In this time, this molten iron alloy is desirable to be the molten iron or chromium-containing molten iron.