Polysulfone membranes for CO2/CH4 separation: State of the art

Abstract

The world market for CO 2 /CH 4 separation using membrane technology is getting bigger and polysulfone (PSf) is one of the most widely investigated polymer membrane materials. However, the existing PSf membranes performances are insufficient to fully exploit these opportunities. Therefore, modification that would produce membrane that fit the needs of target separation performances is a main issue. Firstly, various manufacturing processes to achieve best CO 2 /CH 4 separation performance are discussed, including important post-treatments. The formulation of polymer solution and effects of manufacturing parameters on the resulting membranes are presented. Other modifications, which involved PSf structure modification, PSf-based copolymer, mixed matrix membrane and facilitated transport membrane, are also discussed. Performances of those modified membranes are compared with the Robeson's upper bound and some modifications give satisfying results. Finally, commercial application of PSf membranes for CO 2 /CH 4 separation is discussed.

Various Techniques for Preparation of Thin‐Film Composite Mixed‐Matrix Membranes for CO2 Separation

“…Although several types of polymer‐based TFC‐MMMs have been developed for CO 2 /CH 4 separation, the present TFC‐MMMs are facing two limitations. The first challenge is to acquire a greater selectivity at the minimum or comparable productivity and the second one is the performance stability of TFC‐MMMs in the presence of aggressive and complex feed mixtures . The main issue regarding the asymmetric structure of the composite membrane is the large pore size of a selective layer formed by phase inversion that results in large pore penetration , and pore intrusion problems .…”

Preparation and gas transport properties of dual‐layer polysulfone membranes for high pressure CO2 removal from natural gas

“…This pressure becomes important in practice due to the effect of plasticization phenomenon on membrane selectivity. Membrane with higher plasticization pressure can maintain its selectivity better than membrane with lower plasticization pressure in high CO 2 feed concentration or in high operation pressure …”

Morphology Control of Polysulfone Membranes in Filtration Processes: a Critical Review

“…The market share for the PSU membrane use is continuously increasing, for instance, the PSU is the most widely used membrane for CO 2 /CH 4 separation process due to its low price, chemical stability, and mechanical strength. The world market for natural gas is estimated at approximately US-$ 22 billion annually and as it keeps growing, the market for PSU membrane technology will be increasing as well [7]. Compared to cellulose acetate, PSU has lower CO 2 permeability and CO 2 / CH 4 selectivity but higher plasticization pressure, the pressure at which the permeability starts to increase with increasing the penetrant concentration or pressure [7].…”

“…Compared to cellulose acetate, PSU has lower CO 2 permeability and CO 2 / CH 4 selectivity but higher plasticization pressure, the pressure at which the permeability starts to increase with increasing the penetrant concentration or pressure [7]. Plasticization pressure becomes important in practice due to its effect on membrane selectivity with high CO 2 feed concentration or on high operating pressure [7]. Nevertheless, applications of the PSU membranes in the filtration of aqueous solutions are often limited because of their hydrophobic nature which results in a low permeate flux and significant membrane fouling.…”

“…The world market for natural gas is estimated at approximately US-$ 22 billion annually and as it keeps growing, the market for PSU membrane technology will be increasing as well [7]. Compared to cellulose acetate, PSU has lower CO 2 permeability and CO 2 / CH 4 selectivity but higher plasticization pressure, the pressure at which the permeability starts to increase with increasing the penetrant concentration or pressure [7]. Plasticization pressure becomes important in practice due to its effect on membrane selectivity with high CO 2 feed concentration or on high operating pressure [7].…”