The present invention addresses the problem of providing: a composite hollow-fiber membrane having high permeability and high membrane strength; and a production method therefor. The present invention pertains to a composite hollow-fiber membrane that at least has a layer (A) and a layer (B), wherein the layer (A) contains a thermoplastic resin, the layer (A) is provided with a co-continuous structure comprising voids and a phase containing the thermoplastic resin, the co-continuous structure has a structural cycle of 1-1000 nm, and the hole area rate H.sub.A of the layer (A) and the hole area rate H.sub.B of the layer (B) fulfill the relation: H.sub.A<H.sub.B.

Provided is a porous membrane that can be manufactured in uncomplicated steps, has high hydrophilicity and water permeability, and exhibits excellent anti-fouling properties when used in a membrane bioreactor method (MBR method). The porous membrane of the present invention is a porous membrane containing polymer (A) and polymer (B), wherein the polymer (A) is a membrane-forming polymer, the polymer (B) is a polymer having a unit (b1) represented by formula (1) and a unit (b2) based on hydroxyl group-containing (meth)acrylate, and the concentration (mass %) of the unit (b1) is equal to or higher than the concentration (mass %) of the unit (b2) in the porous membrane.

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Disclosed herein are asymmetric multilayer carbon molecular sieve (CMS) hollow fiber membranes and processes for preparing the membranes. The processes include simultaneously extruding a core dope containing a polymer and suitable nanoparticles, a sheath dope, and a bore fluid, followed by pyrolysis of the extruded fiber.

Problems that the invention is to solve is to provide a composite hollow fiber membrane being excellent in separation performance and permeation performance, having high membrane strength, and capable of being easily produced, and a method for producing the same. The present invention relates to a composite hollow fiber membrane including at least a layer (A) and a layer (B), in which the composite hollow fiber membrane has an outer diameter of 20 to 350 m and an inner diameter of 14 to 250 m, the tensile modulus of the composite hollow fiber membrane is from 1,000 to 6,500 MPa, the layer (A) contains a cellulose ester, the thickness of the layer (A) is from 0.01 to 5 m, and the open pore ratio H.sub.A of the layer (A) and the open pore ratio H.sub.B of the layer (B) satisfy H.sub.A<H.sub.B.

A novel or improved base film for impregnation, impregnated base film, product incorporating the impregnated base film, and/or related methods as shown, claimed or described herein.

A membrane process is provided for separating light olefins from light paraffins to produce a polymer grade light olefin product stream that is about 99.5 mol % ethylene or propylene. The process involves multiple stages to achieve the high purity product and provides for processing hydrocarbon streams that have differing concentrations of light olefins.

Provided is a novel continuous single-step method of manufacturing a multilayer sorbent polymeric membrane having superior productivity, properties and performance. At least one layer of the polymeric membrane comprises sorbent materials and a plurality of interconnecting pores. The method includes: (a) coextruding layer-forming compositions to form a multilayer coextrudate; (b) casting the coextrudate into a film; (c) extracting the film with an extractant; and (d) removing the extractant from the extracted film to form the multilayer sorbent polymeric membrane. The sorbent membrane of this disclosure can find a wide range of applications for use in filtration, separation and purification of gases and fluids, CO.sub.2 and volatile capture, structural support, vehicle emission control, energy harvesting and storage, electrolyte batteries, device, protection, permeation, packaging, printing, and etc.

Multilayer single-bore hollow fibre membranes M or multilayer multi-bore hollow fibre membranes M for ultrafiltration applications are disclosed, comprising at least one hollow fibre membrane substrate S comprising a polymer bulk material P1 and at least one functional layer F disposed on at least the inner surface of the hollow fibre membrane substrate S, wherein the functional layer F comprises at least one polymer P2. The hollow fibre membranes may be used in ultrafiltration methods and filtration modules, in particular for the treatment of waste water.

[Problem to be solved] To provide an ion exchange membrane, a method for producing an ion exchange membrane, and an electrolyzer that enable a reduction in electrolytic voltage when subjected to electrolysis.

[Solution] An ion exchange membrane including:

a membrane main body including a fluorine-containing polymer having an ion exchange group; and

a coating layer arranged on at least one face of the membrane main body;

wherein the coating layer includes inorganic particles and a binder,

a mass ratio of the binder to the total mass of the inorganic particles and the binder in the coating layer is more than 0.3 and 0.9 or less, and

a surface roughness of the coating layer is 1.20 m or more.

A membrane process is provided for separating light olefins from light paraffins to produce a polymer grade light olefin product stream that is about 99.5 mol % ethylene or propylene. The process involves multiple stages to achieve the high purity product and provides for processing hydrocarbon streams that have differing concentrations of light olefins.