Sensitivity analysis of the monoethanolamine degradation model in CO2 capture process

In this research, sensitivity analysis of the rate-based model for CO2 chemical absorption by monoethanolamine has been develop by considering the kinetics of the thermal degradation reactions associated with this amine. The rate-based model presented based on two-film model thatincorporates mass transfer including CO2-MEA chemical reactions and degradation reactions. Equilibrium mass transfer equations for CO2 in liquid film in MATLAB software have been solved with BVP4C instruction with specific boundary conditions, and changes in the concentration of amine and CO2 have been determined with and without regard to the degradation kinetics, which, as expected, was accompanied by drop in amine and decrease carbon dioxide absorption. Further, sensitivity analysis of temperature and amine concentration parameters in both cases was performed with and without degradation kinetics. Temperature sensitivity analysis at 298 K and 333 K and sensitivity analysis for amine concentrations at two concentrations of 20 and 30 wt% were carried out. The results showed that with increasing temperature, the reaction speed increased, which is accompanied by a decrease in the amount of amine in circulation and an increase in the production of degradation products. With decreasing initial amine concentration, the reaction speed decreased, the slope of the amine concentration changes slightly, the CO2 absorption in the liquid film decreased, and the concentration of the products of degradation also reduce.