In this paper,AgBF_4/[emim][BF_4]supported ionic liquid membranes(SILMs)were prepared successfully for CO/N_2 separation using nitrogen pressure immobilization procedures.The incorporation of AgBF_4 could decrease mem...In this paper,AgBF_4/[emim][BF_4]supported ionic liquid membranes(SILMs)were prepared successfully for CO/N_2 separation using nitrogen pressure immobilization procedures.The incorporation of AgBF_4 could decrease membrane weight loss,improve the pressure-resistant ability,and keep the critical pressure(0.45 MPa)of the SILMs.The high viscosity and undissolved Ag BF_4 solids in membrane liquid would disturb gas molecular transport through membrane and give rise to the gas transport resistance.Therefore,the gas permeability decreased remarkably with increasing AgBF_4 carrier content in the membrane.When the molar ratio of AgBF_4 to[emim][BF_4]increased from 0:1 to 0.3:1,the CO/N_2 selectivity of the SILMs showed a great increase from~1 to~9 at 20°C and 0.4 MPa,suggesting that AgBF_4 was an effective carrier for CO facilitated transport.The permeabilities of N_2 and CO increased at higher transmembrane pressure,indicating that molecular transport would dominate the transport process at high pressure.The temperature-dependent gas permeability followed the Arrhenius equation.Moreover,the differences between the activation energies of CO and N_2 became larger after introducing AgBF_4,resulting in more obvious decrease in the CO/N_2 selectivity at higher operating temperature.展开更多
基金Financial support from the National Natural Science Foundation of China(21406235)
文摘In this paper,AgBF_4/[emim][BF_4]supported ionic liquid membranes(SILMs)were prepared successfully for CO/N_2 separation using nitrogen pressure immobilization procedures.The incorporation of AgBF_4 could decrease membrane weight loss,improve the pressure-resistant ability,and keep the critical pressure(0.45 MPa)of the SILMs.The high viscosity and undissolved Ag BF_4 solids in membrane liquid would disturb gas molecular transport through membrane and give rise to the gas transport resistance.Therefore,the gas permeability decreased remarkably with increasing AgBF_4 carrier content in the membrane.When the molar ratio of AgBF_4 to[emim][BF_4]increased from 0:1 to 0.3:1,the CO/N_2 selectivity of the SILMs showed a great increase from~1 to~9 at 20°C and 0.4 MPa,suggesting that AgBF_4 was an effective carrier for CO facilitated transport.The permeabilities of N_2 and CO increased at higher transmembrane pressure,indicating that molecular transport would dominate the transport process at high pressure.The temperature-dependent gas permeability followed the Arrhenius equation.Moreover,the differences between the activation energies of CO and N_2 became larger after introducing AgBF_4,resulting in more obvious decrease in the CO/N_2 selectivity at higher operating temperature.
