On the kinetics of oxidation of liquid copper and copper-sulfur alloys by carbon dioxide

The rates of transfer of oxygen between CO₂-CO gas mixtures and liquid copper and copper-sulfur alloys have been studied by a steady-state electrochemical technique. For sulfur-free stagnant copper, and under the conditions of the experiments, the rates are shown to be controlled by the diffusion of oxygen in the metal. The resulting diffusivities are in close accord with the bulk of the previous determinations. At high sulfur concentrations, the rate is found to be controlled by an interfacial reaction which is first order with respect to the pressure of CO₂ and inversely proportional to the sulfur concentration. The rate constant, in mole (at. pct)cm⁻² s⁻¹ atm⁻¹, is approximately 8 × 10⁻⁹ at 1146°C. Formerly a Graduate Student.