Selection and characterization of phase-change solvent for carbon dioxide capture: precipitating system

Characterization of a precipitating solvent for CO2 capture was performed. Aqueous solution of 5m’ potassium salt of sarcosine (KSar) that was precipitated at CO2 loading of 0.52 was selected. The equilibrium solubility of CO2 in the solution was measured over a range of temperatures from 40 to 120 °C. The SOFT model was implemented to predict the vapor-liquid-solid equilibrium (VLSE) data for the CO2-KSar-H2O system. The vapor pressures of the solution were measured at temperatures between 53 and 130 °C. The heat of absorption was also measured at 40 °C. In addition, the heat of absorption of CO2 in the solution was estimated from the VLSE data by use of the Gibbs- Helmholtz equation and was able to predict well the precipitation occurred in the system.