Article

Preparation of a novel polysulfone/polyethylene oxide/silicone rubber multilayer composite membrane for hydrogen–nitrogen separation

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Abstract

A novel polysulfone/polyethylene oxide/silicone rubber (PSf/PEO/SR) multilayer composite membrane was fabricated by double coating polysulfone substrate membrane with polyethylene oxide and silicone rubber. Gas permeation experiments were performed at 30 °C for hydrogen and nitrogen. PSf/PEO/SR membrane displayed high and steady performance for H2/N2: permeances of H2 and N2 of 49.51 and 0.601 GPU, respectively, and H2/N2 ideal separation factor of 82.3. It was explained that layer interfaces due to the introduction of PEO layer act as the permselective media and are responsible for the higher H2/N2 ideal separation factor which has exceeded the intrinsic permselectivities of the three polymers used in this study.

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... Multilayer thin film composite membranes are prepared for use to improve the gas separation efficiency of thin film composite membranes. Generally, the protective layer is coated on the surface of the selective layer to seal the existing defects and to protect the selective layer from abrasion or detrimental chemical attacks (Liang et al., 2018;Ye et al., 2005). The gutter layer is coated on the surface of substrate to improve the adhesion between substrate and selective layer. ...
... The gutter layer is coated on the surface of substrate to improve the adhesion between substrate and selective layer. Moreover, the gutter layer can minimize the mass transport resistance since it is usually made from highly permeable materials (Liang et al., 2018;Ye et al., 2005). ...
... The selectivities of H 2 /N 2 , CO 2 /CH 4 , and O 2 /N 2 were 100, 50, and 7, respectively (Chung et al., 1999). Ye et al. (Ye et al., 2005) prepared polysulfone/polyethylene oxide/silicone rubber (PSf/PEO/SR) multilayer composite membrane by using the dip-coating method. The PEO layer was selective and the SR layer was used as a protective layer. ...
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