Cross-Linkable Polyimide Membrane for Natural Gas Purification and Carbon Dioxide Plasticization Reduction

摘要

The ability of propanediol monoester cross-linkable (PDMC) polymer to effectively separate CO2 from CH4,and the polymer's stability against plasticization under high CO2 pressures,was investigated.The cross-linked PDMC membranes were found to have significantly higher CO2 permeability and slightly higher selectivity for the CO2/CH4 separation than the un-cross-linked PDMC membranes.Cross-linking temperature was found to have a significant impact on the permeation properties of the membranes.The PDMC membrane permeation results are compared with previous research that uses other cross-linking agents for CO2 plasticization resistance and found to offer an excellent balance between extent of cross-linking and tradeoff between mechanical and transport properties.The cross-linked membranes not only outperform the un-cross-linked membranes with their enhanced transport properties but also provide vastly superior plasticization resistance against aggressive CO2 steams.Un-cross-linked and cross-linked PDMC membranes were characterized via permeation (pure and mixed gas),density,T_g,and sorption measurements.