Water Vapor Separation On N2 Using PEO Containing Block Copolymers and Its Blends with Polyetherimide

Removal of water vapor using polymeric membrane process can be applied in dehydration from flue gas or air humidity control of indoor air. This selective transport is possible due to the higher permeation rate of water vapor compared to the other gas components [1].

In this study, Polyetherimide (PEI) hollow fiber membrane was manufactured by dry/wet phase inversion method. The produced fiber typically has an asymmetric structure; a dense top layer supported by porous, sponge and finger-like substructure [2]. Hollow fiber membrane coated with Polyethylene oxide-poly amide block copolymer (PEBA). PEO based block copolymer provides attractive opportunities for the removal of water vapor. The exact water vapor concentration in the feed, permeate and retentate streams were measured using Humidity transmitter (HMT 34, Finland), respectively. The separation experiments of the the mixture gas of water vapor/N₂ were performed according to the operating pressure, temperature and water vapor activity.

As a result, water removal efficiency was increased with pressure at constant temperature. At the operating pressure and temperature of 8 kg_f/cm² and 90°C, respectively, 90% of water removal efficiency was obtained using PEI hollow fiber composite membrane.

Reference

[1] S.J.Mertz, Water vapor and gas transport though polymeric membranes, Ph.D. Thesis, University of Twente, 2003.

[2] D. H. Kim, Y. M. An, H. D. Jo, J. S. Park, and H. K. Lee (2009) Studies on the N₂/SF₆ Permeation Behaviors Using the Polyethersulfone Hollow Fiber Membranes, (Korean) Membr. J. 19: 244-251.