Journal of Chemical and Engineering Data, Vol.64, No.1, 202-210, 2019
Solubility of CO2 in Molten Li2O-LiCl System: A Raman Spectroscopy Study
The molten Li2O-LiCl system is an important molten salt for CO2 capture and electrochemical transformation. In this study, the solubility of CO2 in Li2O-LiCl with 4-8 wt % concentration of Li2O was studied by Raman spectroscopy using Li2SO4 as the external standard at 873-973 K and under 101.3 kPa of CO2. Results showed that the solubility of CO2 increased with Li2O concentration and reached the maximum value of 0.1105 g(CO2)/g(melt) at 923 K and 8 wt % Li2O. Moreover, the conversion rate of Li2O to Li2CO3 reached 94.19%. The Gibbs free energy of the reaction for Li2O with CO2 to generate Li2CO3 in the Li2O-LiCl melts was determined. The reaction was found to be spontaneous and more likely to occur with increased Li2O concentration.