Abstract:
Air separation for the enrichment of oxygen (O2) and nitrogen (N2) gas has gained substantial importance in both industrial and medical applications. Therefore, it is imperative to separate O2 and N2 gases from air mixture. For this purpose, it is proposed to use composite membrane, which is regarded as one of the most innovative technology in 21st century due to its remarkable characteristics. This research aiming for developing high performance perm-selective composite membrane for O2/N2 gas separation for the commercial applications such as blood oxygenator (Artificial Lungs). In-order to achieve this purpose, initially through theoretical model and experimental phase diagram the selection of polymer, compatibility between the layers and morphology of support membrane were predicted. In second step, PVA support membranes were fabricated using non-solvent induced phase separation (NIPS) process, which have the spongy morphology, accordingly as predicted. Which were then optimized using variation in two main parameters, polymeric concentration and coagulation residence time. In third step, a thin mixed matrix membrane (MMMs) based selective layer was coated on the skin layer of PVA asymmetric membranes, having thickness of 7.06 μm forming a multi-layer composite (MLC) membrane. This MMMs layer was composed of CA/PEG blend with incorporated ZIF-8 particles. Through different characterization, the influence of membrane thickness and PEG addition with respect to gas permeance and mechanical properties were analyzed. In which SEM, XRD, FT-IR and UTM were used to study the morphology, chemical structure, presence of different functional groups and membrane mechanical properties respectively. In gas permeation test, it revealed that by reducing thickness of membrane up-to 7.06 μm and addition of PEG, resulted in maximum O2 gas permeance up-to 0.75 GPU at 2 bar. Which concludes that, by reducing membrane thickness and addition of plasticizer, increases the gas permeance.
