Facilitated transport of CO2 through polyvinylamine/polyethlene glycol blend membranes

Abstract Poly(vinylamine)/poly(ethylene glycol) blend membranes were prepared. The effects of blend polymer composition on the membrane structure and CO 2 /CH 4 separation performance were investigated. The results show that membrane crystallinity are at a minimum against poly(ethylene glycol)(PEG) content, while the permeation rates of CO 2 and CH 4 are the maximum. The blend membrane with 10 wt% PEG has the highest pure CO 2 permeation rate of 5.8×10 −6 cm 3 (STP)/cm 2 .s.cm Hg and the highest selectivity of 63.1 at 25°C and 96 cm Hg of feed pressure. The effects of cross-linking and the coupling effects between CO 2 and CH 4 were also investigated. The selectivity increased remarkably when the membrane is cross-linked. For mixed gas of constant CH 4 partial pressure and changing CO 2 partial pressure, the CH 4 permeation rate increased with an increase of CO 2 partial pressure due to the coupling effects.