Experimental and Thermo-kinetic Study of Ethane Absorption in N-methyl-2-pyrrolidone Solvent

Determining the solubility of gases in solvents and considering non-ideality at different operating conditions are essential to design a cost-effective and energy-efficient absorption process. In this study, using a pressure decaying set-up, the solubility of pure ethane in N-methyl-2-pyrrolidone (NMP) was measured at different temperatures (278.15, 298.15, and 328.15 K) and pressures up to 14 bar, and kinetic and equilibrium results were obtained. Accordingly, the values of Henry’s law constants and also the heat of absorption were calculated at various temperatures. Then, thermodynamic modeling was accomplished by applying the Peng Robinson equation of state (PR-EOS) and the Wilson activity coefficient model, and the binary interaction parameters for this system were estimated. By the thermodynamic modeling, positive deviation from ideal behavior is apparently observed for this system. Due to low absolute average deviation of less than 12.3%, the correlated thermodynamic model is able to predict the ethane solubility in NMP with a reliable accuracy.