Volume 9: Sustainable Energy Solutions for Changing the World: Part I

Evaluation of Diffusivity and solvent concentration effect on intermolecular interaction of secondary and tertiary amines for CO2 absorption process Maimoona Sharif, Xiaomei Wu , Yunsong Yu , Tingting Zhang, Zaoxiao Zhang.

Abstract

Diffusion coefficient study gains an interest to know the mass transfer properties of molecules especially in the study of the absorption process. The main objective of the present study is to investigate the effect of temperature on the diffusivity of the MEA absorption process for CO2 capture and to explore the effect of solvent concentration on intermolecular interactions of 2EAE (2-ethylamino ethanol) and 2DMAE (2-dimethylamino ethanol). The molecular dynamic simulation study is conducted for the calculation of diffusivity and intermolecular interaction of amines. Three different values of process temperature are chosen for calculation of diffusivity i.e. 298 K, 313 K and 318 K. Mean Square Displacement (MSD) analysis was done to compute the diffusion coefficient of molecules in secondary and tertiary amine system. Radial distribution function analysis was carried out for the calculation of intermolecular interactions. The results show that the rate of the diffusion coefficient is increased as temperature is increased and the CO2 diffusivity on MEA is higher as compared to 2DMAE but lower than 2EAE. The diffusivity results obtained from the present work are in good agreement with theoretical results. The results of the main solvent concentration on intermolecular interaction show that by increasing the concentration of the solvent, the intermolecular interaction strength increases in both cases of secondary and tertiary amines. The 30% of 2EAE shows highest intermolecular interactions in CO2 and 40%

Keywords CO2 diffusion coefficient, Molecular dynamic simulation, Mean square displacement, Primary