Facilitated transport of CO2 through Co(II)-S-EPDM ionomer membrane.

A new facilitated transport ionomer membrane was prepared by incorporating Co(II) ions, as fixed carrier, into the sulfonated ethylene-propylene-diene terpolymer, Co(II)-S-EPDM, and was applied for preferential transport of carbon dioxide rather than nitrogen from CO 2 /N 2 gas streams. The membranes were also characterized by using the FTIR, SEM and TG/DSC analyses. Furthermore, single gas permeation experiments at different membrane thicknesses (30 and 200 μm), sulfonic group contents (0.1 and 0.2 mmol of sulfonic acid (SO 3 H)/g EPDM), feed gas pressures (2–10 bar) and temperatures (30–50 °C) were carried out. The permeation results of the dense Co(II)-S-EPDM ionomer membranes show that the incorporation of Co(II) ions into the sulfonated EPDM ionomers increases the permeance of both CO 2 and N 2 gases. Moreover, due to facilitated CO 2 transport by the carriers, the CO 2 /N 2 selectivity is also increased. These are mainly attributed to the formation of polymer coordinate complexes in the ionomer. [ABSTRACT FROM AUTHOR]