Carbon Dioxide Absorption Characteristics in Blended Amine Solutions for Wet Scrubbing Processes

The removal of carbon dioxide using mixed solvents continues to be of interest. A mixed (or blended) solvent can be defined as consisting of chemical-chemical solvents and chemical-physical solvents. In this study, Sulfolane was chosen as the physical solvent because of its stability and outstanding affinity. MEA, DEA, MDEA, DIPA were chosen because they are representative amines and are thermodynamically and kinetically selective for CO2. The solubility of CO2 has been measured from 40 to 130℃ in a various mixing combination of solvents by the static method. In order to overcome non-ideality, activity coefficients and fugacity coefficients were introduced. The activity coefficients also take into account interaction between solute species in the liquid phase. Several reported thermodynamic models have been used to obtain activity coefficient matrices. The fugacity coefficients were also calculated to consider non-ideality of pressure.