The present invention relates to a composite membrane for gas separation and/or nanofiltration of a feed stream solution comprising a solvent and dissolved solutes and showing preferential rejection of the solutes. The composite membrane comprises a separating layer with intrinsic microporosity. The separating layer is suitably formed by interfacial polymerisation on a support membrane. Suitably, at least one of the monomers used in the interfacial polymerisation reaction should possess concavity, resulting in a network polymer with interconnected nanopores and a membrane with enhanced permeability. The support membrane may be optionally impregnated with a conditioning agent and may be optionally stable in organic solvents, particularly in polar aprotic solvents. The top layer of the composite membrane is optionally capped with functional groups to change the surface chemistry. The composite membrane may be cured in the oven to enhance rejection. Finally, the composite membrane may be treated with an activating solvent prior to nanofiltration.

A method for producing a gas separation membrane containing fine particles uniformly dispersed in a resin, including the following (A) and (B): (A) a step of mixing the fine particles with a matrix resin, the amount of the fine particles with respect to the entire mass of the mixture being adjusted to 1 mass % to 50 mass %, to thereby prepare a master batch; and (B) a step including dissolving the master batch in a solvent, applying the prepared solution onto a substrate, and evaporating the solvent.

The present invention provides a composition comprising an organic compound having an acid dissociation constant in a 25° C. aqueous solution of 5.0 to 15.0, a hydrophilic resin, and a basic compound, wherein a content of the organic compound is 30 to 1,000 parts by weight per 100 parts by weight of the hydrophilic resin.

The present invention provides a composition comprising an organic compound having an acid dissociation constant in a 25° C. aqueous solution of 5.0 to 15.0, a hydrophilic resin, and a basic compound, wherein a content of the organic compound is 30 to 1,000 parts by weight per 100 parts by weight of the hydrophilic resin.

A membrane assembly for separating a feed liquid into a permeate and a retentate includes a semipermeable membrane and conductive members for applying a voltage effective for charging a semipermeable surface of the membrane, thereby reducing or preventing fouling or scaling of the membrane. The conductive members may be positioned adjacent to the semipermeable membrane, and may be configured as feed spacers or permeate spacers. Alternatively or additionally, the membrane may be electrically conductive. Power from an external source may be supplied to one or more of the conductive members, or also the membrane if conductive, which may be done wirelessly. One or more membrane assemblies may be provided in a container. One or more membrane assemblies may be provided in a stacked configuration, or wrapped around a tube in a spiral configuration.

A membrane assembly for separating a feed liquid into a permeate and a retentate includes a semipermeable membrane and conductive members for applying a voltage effective for charging a semipermeable surface of the membrane, thereby reducing or preventing fouling or scaling of the membrane. The conductive members may be positioned adjacent to the semipermeable membrane, and may be configured as feed spacers or permeate spacers. Alternatively or additionally, the membrane may be electrically conductive. Power from an external source may be supplied to one or more of the conductive members, or also the membrane if conductive, which may be done wirelessly. One or more membrane assemblies may be provided in a container. One or more membrane assemblies may be provided in a stacked configuration, or wrapped around a tube in a spiral configuration.

A polymer blend membrane includes a polyether-based copolymer and a polyether polymerized in situ and has high permeability and high selectivity for carbon dioxide. In the polymer blend membrane, the free volume of the polyether-based copolymer is greatly increased, and the adsorption capacity for carbon dioxide is enhanced. Thus, it can have excellent mechanical properties and excellent permeability and selectivity for carbon dioxide.

Polymer membranes include a polymer material that is selectively permeable to acidic gases over methane in a gas stream, such as natural gas. The polymer material may be a polymer membrane comprising a fluorinated polytriazole polymer. The fluorinated polytriazole polymer may further comprise a substituted phenyl or a substituted benzenaminyl. The substituted phenyl or substituted benzenaminyl may be substituted with hydrogen, bromo, fluoro, chloro, iodo, hydroxy, methyl, trifluoromethyl, dimethylamino, tert-butyl, or difluoromethoxy groups. The polymer material may have a degree of polymerization of from 100 to 175. The polymer membranes may be incorporated into systems or methods for removing separable gases, such as acidic gases, from gas streams, such as natural gas.

Polymer membranes include a polymer material that is selectively permeable to acidic gases over methane in a gas stream, such as natural gas. The polymer material may be a polymer membrane comprising a fluorinated polytriazole polymer. The fluorinated polytriazole polymer may further comprise a substituted phenyl or a substituted benzenaminyl. The substituted phenyl or substituted benzenaminyl may be substituted with hydrogen, bromo, fluoro, chloro, iodo, hydroxy, methyl, trifluoromethyl, dimethylamino, tert-butyl, or difluoromethoxy groups. The polymer material may have a degree of polymerization of from 100 to 175. The polymer membranes may be incorporated into systems or methods for removing separable gases, such as acidic gases, from gas streams, such as natural gas.

Electroactive polymers having redox activatable moieties pendant from a polymeric backbone, and compositions of the electroactive polymers are disclosed. The polymers are useful in membranes for electrochemical cells, and for facilitation of electrolytically-based carbon dioxide enrichment.