Decompression stripping of carbon dioxide from rich monoethanolamine through porous hydrophobic modified ceramic hollow fiber membrane contactor

Abstract

In this study, commercial alpha alumina powder was used to fabricate hollow fiber membrane by phase inversion spinning method. The fabricated alumina hollow fiber membrane was confirmed to have high chemical and thermal stability based on thermogravimetric analysis and contact angle measurement. When CO2 stripping characteristics were examined by introducing decompression membrane contactor process in the stripping part of amine absorption process, increase in degree of vacuum resulted in increased CO2 stripping flux. In liquid to lumen operation under decompression pressure of 61.325 kPa and absorbent flow rate of 9 ml/min, CO2 stripping flux was 45.75 × 10−4 mol/m2·s. Existing articles on membrane contactor stripping were mostly N2 sweep type and reported CO2 stripping flux of 1–24 mol/m2·s, whereas the present study achieved stripping performance that was approximately 2–40 times higher. Decompression stripping of porous ceramic hollow fiber membrane contactor can be viewed as a promising process since it did not cause the phenomenon of decrease in CO2 purity due to N2 and showed similar or greater CO2 stripping flux than previously reported membrane contactor stripping processes.