Recovery of cobalt and manganese from ash of residue from manufacture of trimellitic acid by acid extraction

摘要

Cobalt and manganese are recovered from incineration ash obtained by combustion of residue from the manufacture of trimellitic acid and its recovery as 4-carboxyphthalic anhydride and then the recovered cobalt is separated from the recovered manganese by magnetic separation. The foregoing is accomplished by extraction of the ash with an aqueous solution of hydrogen bromide or chloride, recovery of the extract solution, and the upward adjustment of its pH while adding powdered manganese to precipitate metallic cobalt for its separation by magnetic means.