Investigation of CO2 Solubility in Blends of AMP and HMDA Solvents: Thermodynamic Modeling Based on the Deshmukh-Mather Model

Abstract

Among the various methods for CO2 removal from the atmosphere, CO2 absorption is considered as the most applicable one. Although several studies have been performed on CO2 absorption by using chemical solvents, there are not many studies on using improved absorbents. Therefore, the aim of this study was to measure the solubility of CO2 in utilized aqueous blends of 2-amino-2-methyl-1-propanol (AMP) and hexamethylenediamine (HMDA). In the present research, the equilibrium set up for measuring CO2 solubility in aqueous solvents was assembled. CO2 solubility experiments were carried out over a various range of CO2 partial pressures (8.44, 25.33, and 42.22 kPa) temperatures (303, 313, and 323 K) and solvent concentration (0.4, 1.8, 2, and 3 M). The results showed that increasing CO2 partial pressure or decreasing the temperature would lead to an increase in CO2 loading. Furthermore, with increasing HMDA concentration, CO2 loading reached a maximum value before it followed a slight decrease. The experimental results were fitted to the thermodynamic Deshmukh Mather model and the required parameters in this model were generated. The results showed that there is a good agreement between theoretical and experimental results of CO2 loading.