Southwire Company, LLC

Robert R Odle

William W Brunson

Milton E Berry

Daniel B Cofer

Maxson L Stewart

Roy Richards

William R Burson

Disclosed is an integrated system for continuously melting and refining secondary and blister copper to produce and continuously cast anode grade copper comprising: continuous melting of secondary and blister copper in an optional fuel vertical shaft furnace; continuously or semicontinuously skimming initial slag from the surface of the melted copper in a slag vessel as it drains from the shaft furnace; collecting a reservoir of molten copper in a holding furnace capable of controlling its temperature and subsequent flow; adding fluxes to the molten copper; directing the molten copper into an oxidation vessel where the molten copper and impurities are oxidized; transferring the oxidized and fluxed molten copper to a second slag vessel where slag is skimmed from its surface; flowing the oxygen rich molten copper into a reduction vessel where oxygen content is reduced; collecting a supply of refined molten copper in a final holding vessel; continuously passing the refined molten copper through a filtering ladle containing ceramic foam molten copper filters; and continuously supplying refined and filtered molten copper to a casting ladle which continuously casts the refined and filtered molten copper into anodes of suitable quality for electrorefining or into a cast product not requiring electrorefining.

Continuous melting and refining of secondary and/or blister copper

A process is provided for purification of nickel sulfate via ammoniacal leaching and pH regulated solvent-extraction, while providing for regeneration of the extractant and the leach solution. The process is especially suited for hydrometallurgical extraction of high purity nickel sulfate from residue resulting in the regeneration of spent electrolyte in the electrorefining of secondary copper. According to the process, the starting material is leached in an ammonia solution of selected pH to solubilize the nickel as polyammine sulfate, followed by extracting the solubilized nickel by pH regulated solvent-extraction. The extractant is then stripped and regenerated with sulfuric acid by first scrubbing in a first pH range to remove ions that are more electropositive than nickel, then stripping with sulfuric acid in a second pH range to remove nickel ions, and then regenerating the extractant by stripping in a third pH range to remove ions that are less electropositive than nickel. Finally, high purity nickel sulfate is crystallized from the nickel-loaded stripping solution. Further, the spent ammonia leach solution is preferably regenerated.

Purification of nickel sulfate

Growing community of inventors

Harvey, LA, United States of America

Robert R Odle