Patent ID: 6395059
Filing Date: 2002-05-28
Classification: C22B

Abstract:
A process for refining either blister copper or molten copper in a copper bath, containing at least S and optionally one or more elements selected from the group consisting of As, Sb, Pb, Ni, Bi, Se, and Te, comprising the steps of:injecting a mixture of air and O2 gas into the copper bath in the presence of an alkali source, and removing SO2 generated in situ, thereby forming an effective amount of a molten alkali sulfate on top of the copper bath; adding an alkali sulfate and/or alkali oxide into the melt to promote scrubbing of one or more elements selected from the group consisting of As and Sb into a solution containing sulfates; increasing oxygen levels in the blister or molten copper to remove impurities one or more impurities selected from the group consisting of Sb, Pb, Ni, Bi, Se and Te by fluxing them into a molten solution of Cu2O and/or Cu2Oâ€”CaO, the molten solution being stable with the sulfate phase; and removing slag from the copper bath.