Carbon dioxide absorption in a gas-liquid membrane contactor: Influence of membrane properties and absorbent chemistry

The present work demonstrates the performance of hollow fibre membranes fabricated using polyvinyl chloride, polystyrene (EPS) and polydimethylsiloxane (PDMS) coupled with 30% monoethanolamine (MEA) in a gas liquid membrane contactor (GLMC) for the absorption of carbon dioxide. A gas mixture with a composition of (50/50 v/v%) methane (CH₄) and (CO₂) was used to assess the efficiency of the prepared membranes in the removal of carbon dioxide. Then HFM 3 which showed high CO₂ removal was used to separate a mixture of nitrogen (N₂)/oxygen(O₂)/carbon dioxide (CO₂) with a composition of (73/18/9 v/v%), respectively. Four different absorption liquids: 30 % MEA solution, 30 % EDA solution, 30 % MEA – graphene oxide (GO) and 30 % EDA-GO nanofluids were coupled with HFM3 to analyse the efficiency of the different amine liquids in CO₂ absorption in GLMC. The 30 % EDA-GO solution showed an increase in the efficiency of CO² absorption. The nanofluids showed an enhancement factor for CO₂ absorption in the nanofluid was 121 % and 117 % for MEA-GO and EDA-GO, respectively. This enhancement was attributed to the hydrodynamic effects and Brownian motion of graphene oxide in the amine liquids. 30 % EDA solution infused with 0.2 mg/ml graphene oxide nanoparticles achieved the highest loading of carbon dioxide 0.25 mol/ cm³.