A New Model for Correlation and Prediction of Equilibrium CO2 Solubility in N-Methyl-4-Piperidinol Solvent

作者：Xiao, Min; Cui, Ding; Liu, Helei^*; Tontiwachwuthikul, Paitoon; Liang, Zhiwu^*

来源：AIChE Journal, 2017, 63(8): 3395-3403.

DOI：10.1002/aic.15709

• CO2 capture
• tertiary amine
• equilibrium solubility
• novel thermodynamic model

In this work, the equilibrium CO2 solubility in the aqueous tertiary amine, N-methyl-4-piperidinol (MPDL) was measured over a range of temperatures, CO2 partial pressures and amine concentrations. The dissociation constant of the MPDL solution was determined as well. A new thermodynamic model was developed to predict the equilibrium CO2 solubility in the MPDL-H2O-CO2 system. This model, equipped with the correction factor (C-f), can give reasonable prediction with an average absolute deviation of 2.0%, and performs better than other models (i.e., KE model, Li-Shen model, and Hu-Chakma). The second-order reaction rate constant (k(2)) of MPDL and the heat of CO2 absorption (-Delta H-abs) into aqueous MPDL solutions were evaluated as well. Based on the comparison with some conventional amines, MPDL revealed a high-equilibrium CO2 loading, reasonably fast absorption rate when compared with other tertiary amines, and a low energy requirement for regeneration. It may, therefore, be considered to be an alternative solvent for CO2 capture.

• 出版日期2017-8
• 单位湖南大学