Copper refining and novel flux therefor

摘要

A method for removing lead and other basic impurities from copper during refining of the copper comprises treating molten copper to be refined with a slag having a final composition including iron oxide, calculated as Fe2O3 and silica (SiO2) wherein the weight ratio of iron oxide to silica is from 0.4 to 0.8. The novel slag preferably contains less than 10% boric oxide and up to 30% phosphorus pentoxide.