Influence of membrane wetting on CO2 capture in microporous hollow fiber membrane contactors

Experimentally, the CO2 absorption in a 2 M DEA solution was found to be influenced by the gas flow rate significantly and the CO2 flux was enhanced by the increase of CO2 volume fraction in the feed stream. Moreover, in the Celgard microporous hollow fiber MiniModule®, the CO2 flux reduced about 20% in the initial 4 days of operation and then there was no change in the performance. The membrane wetting was identified to be the main reason responsible for the performance drop, as the membrane morphology and the overall mass transfer coefficient presented corresponding changes. The retrieval of the CO2 flux to 90% of the original amount was achieved by increasing the gas phase pressure, which further validated this hypothesis. Clearly, the prevention of the membrane wetting is very critical in maintaining the high performance of CO2 absorption in the membrane contactor.