Theoretical studies on separation of CO2 by single and blended aqueous alkanolamine solvents in flat sheet membrane contactor (FSMC)

Absorption of carbon dioxide by different single and blended alkanolamine solvents were studied theoretically using flat sheet membrane contactor. The solvents considered for this study include aqueous solutions of monoethanolamine (MEA), diethanolamine (DEA), N-methyldiethanolamine (MDEA) and 2-amino-2-methyl-1-propanol (AMP) as well as aqueous blends MEA or DEA with AMP or MDEA. Simulation study shows that the absorption flux for CO2 with aqueous solution of MEA was the highest among the single amines solvents studied. There is an increase in CO2 absorption flux with the increase in the concentration of MEA or DEA in the blends of (MEA + MDEA), (DEA + MDEA) and (MEA + AMP). For the (DEA + AMP) system the flux of CO2 is found to have a marginal effect with different blend compositions. The blends of (MEA + MDEA) and (MEA + AMP) are found comparatively suitable for the absorption of CO2 among all the blends. The performance of flat sheet membrane contactor is found to be better than that of hollow fiber membrane contactor if only the absorption flux of CO2 in the amine is considered.