Improving the accuracy of the Eyring equation by pseudo‐ideal solution model to predict the viscosity of the mono‐ethanol amine‐[Bmim] PF6 ionic liquid blends in a CO₂ capturing pilot plant

Abstract

The purpose of the present study was to propose a new simulation model for calculation of the viscosity of the mono-ethanol amine-ionic liquid (MEA-IL) solvent in the CO 2 -capturing pilot plant. To do so, a combination of the pseudo-ideal solution model (PISM) and Eyring's mixture viscosity equation was implemented in MATLAB. Moreover, the various thermodynamic models were used to calculate viscosity, using solvent containing MEA-IL in the high CO 2 feed gas. The present study determined the viscosities of the MEA-IL blends at different concentrations and various temperatures in the CO 2 capturing pilot plant. The results were comparable to those obtained from the Eyring-PISM model, Eyring-Wilson method, Cheng and Meisen a previous study equation, and the Aspen Plus and Promax with electrolyte non-random two-liquid model that presented the actual viscosity values of the liquid solutions. The calculated solvent viscosity values with the Eyring-PISM model at different temperature profiles were achieved using an average absolute deviation (AAD) of about 1.164% and 1.422% in absorber and desorber for solvent (MEA = 27 wt% and IL = 34.2 wt%) and 1.578% and 1.868% in absorber and desorber for solvent (MEA = 29 wt% and IL = 37.12 wt%), respectively. The consideration of a suitable model for the determination of viscosity has a significant role in energy consumption in the CO 2 -capturing pilot plant. The estimated energy consumption with the Eyring-PISM model was achieved using an AAD of about 0.652% for solvent (MEA = 27 wt% and IL = 34.2 wt%) and 0.502% for solvent (MEA = 29 wt% and IL = 37.12 wt%), respectively. The results obtained from the Eyring-PISM simulation model using the experimental data revealed a high degree of accuracy.