| abstract |
A stable high performance facilitated transport membrane comprising an asymmetric integrally-skinned polymeric membrane wherein the pores on the relatively porous, thin, dense skin layer of the membrane comprises a hydrophilic polymer such as chitosan or sodium alginate, a metal salt such as silver nitrate, or a mixture of a metal salt such as silver nitrate and hydrogen peroxide and the asymmetric integrally-skinned polymeric membrane comprises a relatively porous, thin, dense skin layer as characterized by a CO 2 permeance of at least 200 GPU and a CO 2 over CH 4 selectivity between 1.1 and 10 at 50°C under 50-1000 psig, 10% CO 2 /90% CH 4 mixed gas feed pressure. The present invention further includes a method of making these membranes and their use for olefin/paraffin separations, particularly for propylene/propane and ethylene/ethane separations. |