Composite hollow fiber membranes for CO2 capture

For both PVAm/PSf and PVAm/PPO membranes, the CO2 permeance was similar with the CO2 permeance of uncoated hollow fiber supports, confirming that the CO2 diffusion rate limiting step resides in the properties of the relatively thick support, not at the level of 1.2 μm thin and water swollen PVAm selective layer. A dynamic transfer of the CO2 diffusion rate limiting step between PVAm top layer and PPO support was observed by changing the feed relative humidity (RH%). The CO2 diffusion rate was controlled by the PPO support when using humid feed. At low feed humidity the 1.2 μm PVAm top layer becomes the CO2 diffusion rate limiting step.