Modeling pre-combustion CO2 capture with tubular membrane contactor using ionic liquids at elevated temperatures

A pre-combustion carbon capture process at high temperatures in membrane contactor setup using ionic liquid 1-Butyl-3-methlyimidazolium tricyanomethanide ([Bmim][TCM]) as an absorbent was studied here by developing a comprehensive mathematical model. A detailed 2D mass transport model based on finite element analysis was presented for this purpose. The model considers molecular diffusion in both axially and radially. The effects of various operational parameters were studied for CO2 absorption flux. A comparative study was carried out among different membrane contactor modules having different number of fibers. The increase in number of fibers has significantly enhanced the CO2 absorption process. An increase of 31% in the CO2 separation efficiency was observed by increasing the number of fibers from 1 to 10. Furthermore, the transient state behavior of CO2 concentration during the absorption process until reaching a steady state was systematically studied for various operating temperatures and gas flow rates.