Kinetic Study on Bismuth Removal from Molten Copper Matte by Ar + O_2 Gas Bubbling

摘要

A kinetic study on Bi removal during copper matte oxidation was designed under the presumptions of low FeO activity and of no fayalite slag formation. Copper matte with 59 wt percent Cu was oxidized by bubbling Ar + O_2 mixture gas through a submerged nozzle. The effects of melt temperature, gas flow rate and oxygen partial pressure on the volatilization rate of Bi in copper matte are discussed. Bi was significantly removed during Ar gas blowing, and the volatilization rate of Bi was markedly increasing with the melt temperature. However, the dependence of the volatilization rates on the oxygen partial pressure was affected in a complicated way by the effects of the melt temperature and the reduced amount of exhausted gas. The volatilization of Bi in copper matte was primarily controlled by the mass transfer rate through the gas film boundary layer around rising gas bubbles.