Abstract: A high performance facilitated transport membrane comprising a metal cation exchanged/chelated carboxylic acid functional group containing functional polyimide, a method of making this a membrane, and the use of this membrane for olefin/paraffin separations, particularly for propylene/propane and ethylene/ethane separations. The facilitated transport membrane has either an asymmetric integrally skinned membrane structure or a thin film composite membrane structure, wherein the top selective layer of the membrane comprises a metal cation exchanged/chelated carboxylic acid functional group containing functional polyimide.

Abstract: This invention provides a new facilitated transport membrane comprising a relatively hydrophilic, very small pore, nanoporous support membrane, a hydrophilic polymer inside the very small nanopores on the skin layer surface of the support membrane, a thin, nonporous, hydrophilic polymer layer coated on the surface of the support membrane, and metal salts incorporated in the hydrophilic polymer layer coated on the surface of the support membrane and the hydrophilic polymer inside the very small nanopores, a method of making this membrane, and the use of this membrane for olefin/paraffin separations, particularly for C3=/C3 and C2=/C2 separations.

Abstract: An asymmetric integrally-skinned flat sheet membrane comprising a miscible blend of an aromatic polyethersulfone (PES) polymer and an aromatic polyimide polymer is used for gas separations such as hydrogen purification, separation of hydrogen and methane and to separate other gases and liquids. UV radiation may be applied to the surface of the membrane for improved properties.

Abstract: The present invention provides high permeance copolyimide membranes and methods for making and using these membranes for gas separations such as for hydrogen purification and for acid gas removal from natural gas. The random copolyimide polymers used to make the copolyimide membrane may be UV crosslinked to improve selectivity in separating mixtures of gases or in purifying liquids. The membranes may be fabricated into any known membrane configuration such as a flat sheet or a hollow fiber.

Abstract: The present invention provides high flux aromatic alkyl-substituted polyethersulfone membranes and methods for making and using these membranes for gas separations. The membranes may be fabricated into any known membrane configuration including a flat sheet or a hollow fiber. The present invention also provides high selectivity UV cross-linked aromatic alkyl-substituted polyethersulfone membranes and methods for making and using these membranes for gas separations.

Abstract: The present invention provided a high temperature resistant epoxy resins for producing hollow fiber membrane modules for high temperature gas separation applications such as for natural gas upgrading and hydrogen purifications. This invention also relates to a hollow fiber membrane module comprising a bundle of multiple high performance hollow fiber membranes and a tube sheet formed by a high temperature resistant cured epoxy resin that is used to fix and bound said bundle of multiple high performance hollow fiber membranes. The invention also provides a process for separating at least one gas from a mixture of gases using the hollow fiber membrane modules comprising a bundle of multiple high performance hollow fiber membranes and a tube sheet formed by a high temperature resistant cured epoxy resin that is used to fix and bound said bundle of multiple high performance hollow fiber membranes.

Abstract: This invention relates to aromatic block copolyimide polymers comprising both hydroxyl functional groups and carboxylic acid functional groups, their membranes and methods for making and using these polymers and membranes. The aromatic block copolyimide polymer described in the present invention comprises both hydroxyl functional groups and carboxylic acid functional groups. The gas transport properties particularly the selectivities of the aromatic block copolyimide comprising both hydroxyl functional groups and carboxylic acid functional groups were significantly improved compared to those of the aromatic random copolyimide comprising both hydroxyl functional groups and carboxylic acid functional groups.

Abstract: The present invention provides a high selectivity epoxysilicone-cross-linked polyimide membrane comprising a polyimide polymer with hydroxyl functional groups cross-linked with epoxy functional groups on epoxysilicone polymer. The present invention also provides a process for separating at least one gas from a mixture of gases using the high selectivity epoxysilicone-cross-linked polyimide membrane. The process comprises providing the high selectivity epoxysilicone-cross-linked polyimide membrane which is permeable to the at least one gas; contacting the mixture on one side of the membrane to cause the at least one gas to permeate the membrane; and removing from the opposite side of the membrane a permeate gas composition comprising a portion of the at least one gas which permeated the high selectivity epoxysilicone-cross-linked polyimide membrane.

Abstract: The present invention provides high permeance copolyimide membranes and methods for making and using these membranes for gas separations such as for hydrogen purification and for acid gas removal from natural gas. The random copolyimide polymers used to make the copolyimide membrane may be UV crosslinked to improve selectivity in separating mixtures of gases or in purifying liquids. The membranes may be fabricated into any known membrane configuration such as a flat sheet or a hollow fiber.

Abstract: The present invention provides high flux aromatic alkyl-substituted polyethersulfone membranes and methods for making and using these membranes for gas separations. The membranes may be fabricated into any known membrane configuration including a flat sheet or a hollow fiber. The present invention also provides high selectivity UV cross-linked aromatic alkyl-substituted polyethersulfone membranes and methods for making and using these membranes for gas separations.

Abstract: The present invention provides a high selectivity epoxysilicone-cross-linked polyimide membrane comprising a polyimide polymer with hydroxyl functional groups cross-linked with epoxy functional groups on epoxysilicone polymer. The present invention also provides a process for separating at least one gas from a mixture of gases using the high selectivity epoxysilicone-cross-linked polyimide membrane. The process comprises providing the high selectivity epoxysilicone-cross-linked polyimide membrane which is permeable to the at least one gas; contacting the mixture on one side of the membrane to cause the at least one gas to permeate the membrane; and removing from the opposite side of the membrane a permeate gas composition comprising a portion of the at least one gas which permeated the high selectivity epoxysilicone-cross-linked polyimide membrane.

Abstract: The present invention provided a high temperature resistant epoxy resins for producing hollow fiber membrane modules for high temperature gas separation applications such as for natural gas upgrading and hydrogen purifications. This invention also relates to a hollow fiber membrane module comprising a bundle of multiple high performance hollow fiber membranes and a tube sheet formed by a high temperature resistant cured epoxy resin that is used to fix and bound said bundle of multiple high performance hollow fiber membranes. The invention also provides a process for separating at least one gas from a mixture of gases using the hollow fiber membrane modules comprising a bundle of multiple high performance hollow fiber membranes and a tube sheet formed by a high temperature resistant cured epoxy resin that is used to fix and bound said bundle of multiple high performance hollow fiber membranes.

Abstract: This invention relates to aromatic block copolyimide polymers comprising both hydroxyl functional groups and carboxylic acid functional groups, their membranes and methods for making and using these polymers and membranes. The aromatic block copolyimide polymer described in the present invention comprises both hydroxyl functional groups and carboxylic acid functional groups. The gas transport properties particularly the selectivities of the aromatic block copolyimide comprising both hydroxyl functional groups and carboxylic acid functional groups were significantly improved compared to those of the aromatic random copolyimide comprising both hydroxyl functional groups and carboxylic acid functional groups.

Abstract: A copolyimide polymer membrane is provided for separation of hydrocarbons including separation of olefins from paraffins and isoparaffins from other paraffins. The copolyimide polymer membranes include a poly(3,3?-diaminobenzophenone-3,3?,5,5?-tetramethyl-4,4?-methylene dianiline-pyromellitic dianhydride) (abbreviated as poly(DAB-TMMDA-PMDA)). The copolyimide membranes prepared from poly(DAB-TMMDA-PMDA) with varying molar ratios of DAB to TMMDA (abbreviated as PI-DAB-T) showed excellent separation properties for propylene/propane separation.

Abstract: A method for separation of liquid mixtures with a polybenzoxazole (PBO) membrane from a self-cross-linked aromatic polyimide polymer membrane is provided.

Abstract: The polyimide blend membrane in the present invention was prepared by blending a first aromatic polyimide with high permeability and a second aromatic polyimide with high selectivity for gas separation. The polyimide blend membrane in the present invention showed improved permeability compared to membranes made from the second aromatic polyimide and improved selectivity compared to membranes made from the first aromatic polyimide.

Abstract: The polyimide blend membrane in the present invention was prepared by blending a first aromatic polyimide with high permeability and a second aromatic polyimide with high selectivity for gas separation. The polyimide blend membrane in the present invention showed improved permeability compared to membranes made from the second aromatic polyimide and improved selectivity compared to membranes made from the first aromatic polyimide.

Abstract: Polyimide membranes are provided that provide extremely high permeability. The polyimides do not contain carbonyl or sulfonyl functional groups. These membranes are useful in separating gases including the separation of gas pairs including carbon dioxide/methane, hydrogen/methane and propylene/propane as well as other gas mixtures. The membrane selectivity can be adjusted by exposure to ultraviolet light.

Abstract: Polyimide membranes are provided that provide extremely high permeability. The polyimides do not contain carbonyl or sulfonyl functional groups. These membranes are useful in separating gases including the separation of gas pairs including carbon dioxide/methane, hydrogen/methane and propylene/propane as well as other gas mixtures. The membrane selectivity can be adjusted by exposure to ultraviolet light.

Abstract: The polyimide blend membrane in the present invention was prepared by blending a first aromatic polyimide with high permeability and a second aromatic polyimide with high selectivity for gas separation. The polyimide blend membrane in the present invention showed improved permeability compared to membranes made from the second aromatic polyimide and improved selectivity compared to membranes made from the first aromatic polyimide.