RECOVERY OF NONFERROUS METALS FROM METAL-FINISHING INDUSTRY WASTES

Flexible schemes have been devised for recovery of nonferrous metals (copper, chromium, nickel and zinc) from metal finishing industry waste acids and hydroxide sludges. Evaluations conducted with bench scale experimentation established technical feasibility for adaptations of solvent extraction, precipitation and ion exchange separation processes. It was demonstrated with industrial waste samples that by tailoring several separation stages appropriate for specific waste compositions for complex mixtures of widely varying character that efficient separations can be achieved for copper, chromium, nickel or zinc from contaminant metals such as aluminum, chromium or iron.