According to one embodiment, a separator is provided. The separator includes a composite membrane. The composite membrane includes a substrate layer, a first composite layer, and a second composite layer. The first composite layer is located on one surface of the substrate layer. The second composite layer is located on the other surface of the substrate layer. The composite membrane has a coefficient of air permeability of 1×10.sup.−14 m.sup.2 or less. The first composite layer has a first surface and a second surface. The first surface is in contact with the substrate layer. The second surface is located on an opposite side to the first surface. Denseness of a portion including the first surface is lower than denseness of a portion including the second surface in the first composite layer.

A high-performance thin-film composite polyamide membrane upcycled from a substrate fouled with a biopolymer and a preparation method thereof are provided. The method includes fouling the substrate preferably with the biopolymer to obtain a composite of the substrate and a biopolymer foulant layer; then immersing the composite into a first solution formed by dissolving a polyamine monomer in water, followed by taking the composite out of the first solution and removing excess droplets from a surface of the composite; then immersing the composite treated in the previous step into a second solution formed by dissolving an acyl chloride monomer in n-hexane for interfacial polymerization to form a rejection layer on the surface of the composite; and after completion of the reaction, taking the composite out of the second solution, followed by drying and heat treatment, to obtain the target polyamide membrane.

A method produces a metal-organic framework on a surface of another metal-organic framework. One embodiment comprises contacting the first metal-organic framework with a ligand and solvent solution; wherein the first metal-organic framework comprises a first ligand and a first metal; wherein the ligand and solvent solution comprises a second ligand that is different from the first ligand in the first metal-organic framework; and allowing the second ligand from the ligand and solvent solution to exchange with the first ligand present in the first metal-organic framework for a period of time suitable to produce the second metal-organic framework on the surface of the first metal-organic framework.

A method produces a metal-organic framework on a surface of another metal-organic framework. One embodiment comprises contacting the first metal-organic framework with a ligand and solvent solution; wherein the first metal-organic framework comprises a first ligand and a first metal; wherein the ligand and solvent solution comprises a second ligand that is different from the first ligand in the first metal-organic framework; and allowing the second ligand from the ligand and solvent solution to exchange with the first ligand present in the first metal-organic framework for a period of time suitable to produce the second metal-organic framework on the surface of the first metal-organic framework.

The purpose of the present invention is to provide a composite semipermeable membrane whose water permeability is hard to decline even when exposed to high temperature environment for a long period of time, a spiral wound separation membrane element using the composite semipermeable membrane, and a method for producing the same. Another purpose of the invention is to provide a method for evaluating water permeation performance of a composite semipermeable membrane, which method evaluates whether the water permeability of a composite semipermeable membrane is likely to decline due to heat, by a simple evaluation method. The composite semipermeable membrane having a skin layer that includes a polyamide resin, the skin layer being placed on a porous support and having an elastic modulus of 100 MPa or more, calculated by AFM force curve measurement in water.

A silica membrane filter 10 includes an ultrafiltration membrane 15, which is disposed on a support body 14 and which contains an element 14 as a primary component, and a silica membrane 18 which is disposed on the ultrafiltration membrane 15 and which has an aryl group. The ultrafiltration membrane 15 has a structure infiltrated by Si of the silica membrane 18, the atomic ratio A (=Si/M) of Si to the element M in a membrane-side region 16, which is a region corresponding to 25% of the ultrafiltration membrane 15 from the silica membrane 18, satisfies 0.01≦A≦0.5, and the ratio A/B of the atomic ratio A to the atomic ratio B (=Si/M) in a base-material-side region 17, which is a region corresponding to 25% from the support body 14, is within the range of 1.1 or more.

A silica membrane filter 10 includes an ultrafiltration membrane 15, which is disposed on a support body 14 and which contains an element 14 as a primary component, and a silica membrane 18 which is disposed on the ultrafiltration membrane 15 and which has an aryl group. The ultrafiltration membrane 15 has a structure infiltrated by Si of the silica membrane 18, the atomic ratio A (=Si/M) of Si to the element M in a membrane-side region 16, which is a region corresponding to 25% of the ultrafiltration membrane 15 from the silica membrane 18, satisfies 0.01≦A≦0.5, and the ratio A/B of the atomic ratio A to the atomic ratio B (=Si/M) in a base-material-side region 17, which is a region corresponding to 25% from the support body 14, is within the range of 1.1 or more.

A curable composition comprising the components (i) 0 to 60 wt % non-ionic crosslinker(s); (ii) 20 to 85 wt % curable ionic compound(s) comprising an anionic group and at least one ethylenically unsaturated group; (iii) 15 to 45 wt % solvent(s); (iv) 0 to 10 wt % of photoinitiator(s); and (v) 2 to 45 wt % of structure modifier(s); wherein the molar ratio of component (v):(ii) is 0.25 to 0.65. The compositions are useful for preparing membranes for (reverse) electrodialysis.

A composite molecular sieve membrane, preparation method and use thereof are provided in the embodiments. The composite molecular sieve membrane includes a support layer and a molecular sieve membrane layer, wherein the support layer is a high-porosity and porous ceramic which is made of nano- or submicron ceramic powder materials or ceramic material precursors prepared through an electrospinning process. The high-porosity and porous ceramic, is adjustable from 40% to 83%. The composite molecular sieve membrane of the embodiments uses the porous ceramic prepared through an electrospinning process as the support layer, and the support layer has a flat and continuous surface, high porosity, uniform and adjustable pore sizes, low-tortuosity pore channels, and high mechanical strength; the flux of the composite molecular sieve membrane is increased, besides, the seed crystals can attach effectively due to the fibrous pore channels of the support layer, ensuring the adhesion amount of seed crystals.

A composite molecular sieve membrane, preparation method and use thereof are provided in the embodiments. The composite molecular sieve membrane includes a support layer and a molecular sieve membrane layer, wherein the support layer is a high-porosity and porous ceramic which is made of nano- or submicron ceramic powder materials or ceramic material precursors prepared through an electrospinning process. The high-porosity and porous ceramic, is adjustable from 40% to 83%. The composite molecular sieve membrane of the embodiments uses the porous ceramic prepared through an electrospinning process as the support layer, and the support layer has a flat and continuous surface, high porosity, uniform and adjustable pore sizes, low-tortuosity pore channels, and high mechanical strength; the flux of the composite molecular sieve membrane is increased, besides, the seed crystals can attach effectively due to the fibrous pore channels of the support layer, ensuring the adhesion amount of seed crystals.