Kinetics of Deoxidation of the Molten Blister Copper by Bubbling a Carbon Monoxide and Argon Gas Mixture

A kinetic study was investigated the deoxidation of molten blister copper by bubbling an Ar–CO gas mixture through a submerged nozzle at 1,473 K. The effects of CO gas partial pressure and total gas flow rate were thoroughly investigated. The deoxidation rate increased with the CO partial pressure and total gas flow rate. Furthermore, a mathematical model of the mass transfer rate of reactants and products around the boundary layer of rising bubble was constructed. The deoxidation rate highly depended on the mass transfer of reactants and products through the boundary layer. And the experimental results were well explained by this model. The variation in the rate of CO gas supply per unit time under different reaction conditions was disregarded to analyze oxygen concentration reduction and mass transfer resistances comparatively. As a result, it was determined that the chemical reaction at the reaction interface achieved local chemical equilibrium. Moreover, the mass transfer driving force of CO and CO₂ gas significantly influenced the reaction rate under the given conditions. Consequently, it was found that the rate of deoxidation of molten copper through CO gas had a mixed control mechanism involving the mass transfer through both liquid and gas boundary layers.