Microporous polypropylene hollow fiber membranes contactor for the separation and fixation of carbon dioxide from simulative flue gas

In this work, polypropylene hollow fiber membrane (PPHFM) contactor, with aqueous solution absorbent such as sodium hydroxide (NaOH), monoethanolamine (MEA) and diethanolamine (DEA), was designed and used to separate and fix CO2 from CO2/N-2 gas mixtures. The factors that influence the separation properties of CO2/N-2 were investigated for PPHFM contactor studied in this work. It was found that the CO2 removal efficiency is the best by using MEA solution as absorbent. The overall mass transfer coefficient (K) increased with the increase of liquid flow, gas flow and the concentration of the absorbent; however, it decreased with the carbon dioxide concentration in the gas mixture and the temperature of the absorbent solution. Preliminary results showed that carbon dioxide could be fixed efficiently into sodium carbonate and/or sodium bicarbonate with NaOH as the absorbent in the membrane contactor. Pure carbon dioxide, on the other hand, could be produced when MEA or DEA was used as the absorbent.