To provide an electrolyte membrane that exhibits high proton conductivity even at low humidity, the electrolyte membrane includes a composite membrane including: a microporous polyolefin membrane that has an average pore diameter of 1 to 1000 nm and a porosity of 50 to 90% and that can be impregnated with a solvent having a surface free energy of 28 mJ/m.sup.2 or more, and an electrolyte containing a perfluorosulfonic acid polymer having an EW of 250 to 850 loaded into the pores of the microporous polyolefin membrane, wherein the membrane thickness of the composite membrane is 1 to 20 μm.

Durable asymmetric composite membranes consisting essentially of a film of cross-linked sulfonated poly(ether ether ketone) adhered to a sheet of hydrophilicitized microporous poly(ethylene) are disclosed. The membranes have application in the recovery of water from feed streams where the ability to clean in situ is desirable, for example in dairy processing. Methods of preparing cross-linked sulfonated poly(ether ether ketone) suitable for use as the rejection layer and hydrophilicitized sheets of microporous poly(ethylene) suitable for use as the support layer of such membranes are also disclosed.

A membrane comprising chitosan for use in Reverse Osmosis (RO) desalination, or for extracting economically valuable materials from seawater or another highly saline industrial fluid using a thin film composite (TFC) membrane porous support layer comprising chitosan, or for reducing the saline content of one or more industrial or mining fluids for hazardous waste disposal in operations such as desalinization or hydraulic fracturing fracking using a thin film composite (TFC) membrane porous support layer comprising chitosan. The chitosan-based membrane may also be used as part of a dialytic membrane electrode assembly for use in the generation and storing of low across membrane voltages and currents across a salinity concentration gradient.

To provide a catalyst layer, a catalyst layer forming liquid, and a membrane electrode assembly, capable of forming a fuel cell excellent in power generation efficiency.

The catalyst layer of the present invention comprises a supported catalyst having a carrier containing a metal oxide and a catalyst supported on the carrier; and a polymer having at least one type of units containing a cyclic ether structure, selected from the group consisting of units (u11), units (u12), units (u21) and units (u22), and having an ion-exchange group, wherein the total of the content of the units containing a cyclic ether structure is at least 30 mol % to all units which the polymer contains:

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To provide a catalyst layer, a catalyst layer forming liquid, and a membrane electrode assembly, capable of forming a fuel cell excellent in power generation efficiency.

The catalyst layer of the present invention comprises a supported catalyst having a carrier containing a metal oxide and a catalyst supported on the carrier; and a polymer having at least one type of units containing a cyclic ether structure, selected from the group consisting of units (u11), units (u12), units (u21) and units (u22), and having an ion-exchange group, wherein the total of the content of the units containing a cyclic ether structure is at least 30 mol % to all units which the polymer contains:

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Embodiments provide a redox flow battery, an ion exchange membrane for use in the redox flow battery and a method for producing the ion exchanger membrane. The ion exchange membrane includes a base layer, a first hydrophobic layer, and a second hydrophobic layer. The base layer includes sulfonated poly(ether ether ketone). The base layer has a first surface and a second surface. The first hydrophobic layer includes a polydimethylsiloxane elastomer. The first hydrophobic layer is positioned on the first surface of the base layer. The second hydrophobic layer includes the polydimethylsiloxane elastomer. The second hydrophobic layer is positioned on the second surface of the base layer. The ion exchange membrane is configured to prevent cross contamination of the first electrolyte and the second electrolyte. The redox flow battery includes a first half-cell, a second half-cell, and the ion exchange membrane. The first half-cell includes a first electrolyte. The second half-cell includes a second electrolyte. The first half-cell and the second half-cell are configured to undergo a redox reaction to discharge and charge the redox flow battery.

Embodiments provide a redox flow battery, an ion exchange membrane for use in the redox flow battery and a method for producing the ion exchanger membrane. The ion exchange membrane includes a base layer, a first hydrophobic layer, and a second hydrophobic layer. The base layer includes sulfonated poly(ether ether ketone). The base layer has a first surface and a second surface. The first hydrophobic layer includes a polydimethylsiloxane elastomer. The first hydrophobic layer is positioned on the first surface of the base layer. The second hydrophobic layer includes the polydimethylsiloxane elastomer. The second hydrophobic layer is positioned on the second surface of the base layer. The ion exchange membrane is configured to prevent cross contamination of the first electrolyte and the second electrolyte. The redox flow battery includes a first half-cell, a second half-cell, and the ion exchange membrane. The first half-cell includes a first electrolyte. The second half-cell includes a second electrolyte. The first half-cell and the second half-cell are configured to undergo a redox reaction to discharge and charge the redox flow battery.

The present invention relates to a method for preparing a porous polyimide film, comprising reacting an aromatic dianhydride with one or more aromatic diamines in a suitable solvent to form poly(amic acid), adding a dehydrated agent of an acid anhydride and an organic base to the reaction mixture to convert the poly(amic acid) to a polyimide precursor, casting the reaction mixture comprising the polyimide precursor onto a solid support to form a film, coagulating the polyimide precursor in a coagulating bath comprising a mixture of a solvent and a non-solvent to develop a porous structure, and drying the coagulated polyimide precursor in air to form the porous polyimide film. A composite membrane comprising same and its use are also provided.

The present invention relates to a method for preparing a porous polyimide film, comprising reacting an aromatic dianhydride with one or more aromatic diamines in a suitable solvent to form poly(amic acid), adding a dehydrated agent of an acid anhydride and an organic base to the reaction mixture to convert the poly(amic acid) to a polyimide precursor, casting the reaction mixture comprising the polyimide precursor onto a solid support to form a film, coagulating the polyimide precursor in a coagulating bath comprising a mixture of a solvent and a non-solvent to develop a porous structure, and drying the coagulated polyimide precursor in air to form the porous polyimide film. A composite membrane comprising same and its use are also provided.

A direct isopropanol fuel cell adapted for use in ambient conditions and utilizing as fuel isopropanol and water preferably with isopropanol at relatively high concentrations representing 30% to 90% isopropanol.