Hypothesis: The global warming, driven by CO₂ emissions, necessitates urgent mitigation strategies. CO₂ capture using liquid absorbents (such as water) has emerged as a promising approach and the membrane contactors enhance the CO₂ removal. However, the membrane wetting remains a major challenge, typically addressed by using hydrophobic polymers. Despite their effectiveness, these polymers have limited diversity and are non-biodegradab
Methods: Poly(lactic acid) (PLA) membrane, fabricated from a biodegradable polymer derived from renewable resources, was used as a sustainable alternative The PLA membrane was fabricated using the common phase inversion method and
the characterization tests were done. The CO₂ absorption performance was assessed in a flat-sheet membrane contactor and the long-term performance was studied over six days
Findings: The PLA membrane exhibited moderate hydrophobicity with a contact angle of 76.01° and a liquid entry pressure of 2.5 bar. The scanning electron microscopy images confirmed the presence of a finger-like porous structure, facilitating efficient mass transfer. In short-term CO2 absorption tests at liquid velocity of 0.06 m/s,
the absorption rates were 0.0688 mol/m².s and 0.0541 mol/m².s for synthetic seawater (40,000 ppm NaCl) and distilled water, respectively as the absorbents. The long-term test over six days showed performance decline to 0.0479 mol/m².s (30.32% reduction) for seawater and 0.0283 mol.m².s (47.74% reduction) for distilled water. The superior stability observed with seawater was attributed to its higher surface tension, which delayed the membrane wetting and preserved the gas liquid interface. These results demonstrated the potential of PLA membranes for CO₂ absorption applications, particularly when combined with high-salinity absorbents offering an environmentally friendly option for capture technologies