Thermodynamic simulation of oxide ionic equilibria in mixtures of alkali element carbonates

The thermodynamic simulation of equilibriums in the system O2 + СO2 gas mixture – molten alkali carbonates has been performed. Two schemes were proposed to calculate the chemical equilibriums: CO32- = О2- + CO2, O22- = O22- + 1/2O2, 2O2- = О2- + 3/2O2. Concentrations of oxide, peroxide and superoxide ions and standard electrode potentials were calculated as a function of melt composition, partial pressure of O2 and CO2 . Solubility of molecular oxygen was assessed using hard-sphere based scheme. Results of the simulation were compared with the data obtained through conventional thermodynamic calculations and with experiment.