Gas Permeation Performance of Poly(lactic acid) Asymmetric Membrane for O2/N2 Separation

The influence of polymer concentration on the morphology and mechanical properties of asymmetric polyvinyl alcohol (PVA) membrane for O2/N2 separation

“…For these reasons, it is currently not readily evaluated further in a gas separation process. 14 Based on these results of the gas permeation investigation, it can be concluded that the PVA 3H-12 asymmetric membrane has the optimum GS properties and potential for O 2 /N 2 separation.…”

“…According to these results, the gas permeance increases with an increment in pressure, which is attributed to the increase in driving forces for both gases passing across the membrane. 14 The PVA 3H-10 membrane showed the highest permeance of both O 2 and N 2 gas as compared to the PVA 3H-12 membrane. However, in this case, the membrane showed distinctive voids formation in the skin layer and had selectivity in the range of 0.90-0.95, indicating the gas transport was predominantly determined by the pore flow.…”

“…This result also proves the inverse relation of the gas molecular size with its diffusion coefficient. 14,15 This gas separation performance of the PVA asymmetric membrane is expected to be further improved by increasing the concentration up to 14 wt.%. Although at this concentration, the membrane has a higher tensile strength, it also loses elasticity due to the increment of polymeric concentration up to 14 wt.%.…”

“…However, the asymmetric membranes with 21 wt.% had the optimal morphology with improved mechanical strength, which possessed a maximum selectivity (O 2 /N 2 ) of 1.43 and an O 2 gas permeance of 11.33 GPU. Similarly, F. Mohamed et al 14 research group studied Poly (lactic acid) – PLA asymmetric membranes for O 2 /N 2 separation, prepared at different concentrations from 15 to 25 wt.% by using dichloromethane as a solvent and water as a coagulant in the dry/wet phase inversion method. According to their studies, increasing PLA concentration resulted in a decrease in membrane porosity and an increase in membrane compactness and mechanical strength.…”