Provided are a hydrophilic porous membrane including a porous membrane and a hydroxyalkyl cellulose retained in the porous membrane, in which the average pore size differs between two surfaces of the porous membrane, the hydroxyalkyl cellulose distributed in the thickness direction of the hydrophilic porous membrane exhibits two or more peaks of detection intensity in GPC, and the weight-average molecular weight Mw.sub.min of the peak that is detected latest among the above-mentioned peaks is less than 100,000; and a method for producing a hydrophilic porous membrane, the method including separately preparing a hydrophilizing liquid including a hydroxyalkyl cellulose having a smaller weight-average molecular weight and a hydrophilizing liquid including a hydroxyalkyl cellulose having a larger weight-average molecular weight, and applying each of the hydrophilizing liquids on two surfaces of the porous membrane or sequentially on one surface thereof.

A membrane distillation (MD) system consisting of a membrane module and carbon nanotube immobilized membrane for organic solvent separation is disclosed. The MD module includes a feed inlet and outlet, a sweep gas inlet, and a sweep gas outlet. Thermostats are positioned at the feed inlet and outlet to measure the change in temperature. Preferential sorption of the organic on carbon nanotube immobilized membrane contributes to enhanced solvent removal of the MD system. A pervaporation (PV) system consisting of a membrane module and polyvinyl alcohol (PVA) mixed matrix membranes with graphene oxide (GO)—carbon nanotubes (CNTs) for enhanced purification of the alcohol solution after membrane distillation to remove trace amount of water is disclosed.

A gas separation membrane, methods of forming the membrane, and methods of using the membrane for gas separation are provided. An exemplary gas separation membrane includes a cellulosic matrix and a polymer of intrinsic microporosity (PIM). The PIM includes chains coupled by a heat-treating under vacuum.

Stable maintenance of high separation performance of a separation membrane having a separation layer comprising a compact carbon layer is described in addition to a separation membrane having a separation layer comprising a compact carbon layer, wherein particles are attached to the compact carbon layer, recesses are present in the compact carbon layer, and the particles are at least partially stuck in the recesses.

A hollow fiber porous membrane includes polyethersulfone or polysulfone. The hollow fiber porous membrane has an inner diameter from 300 to 600 μm, a thickness from 70 to 200 μm, a molecular weight cut-off of 10000 or lower, and a plurality of pores having a pore diameter from 0.1 to 0.5 μm throughout an outer surface; and a swelling rate of less than 5% as defined below: Swelling Rate (%): for 20 or more of the hollow fiber porous membranes, after a membrane thickness in a cross section of each one of the hollow fiber porous membranes in the width direction is measured at randomly selected 10 or more locations, an average membrane thickness is calculated based on 200 or more locations in total, and the swelling rate is calculated by a formula below: Swelling Rate (%)=(location numbers where the membrane thickness as measured exceeded 1.3 times the average membrane thickness)/(membrane thickness measurement numbers)×100.

A gas separation membrane, methods of forming the membrane, and methods of using the membrane for gas separation are provided. An exemplary gas separation membrane includes a cellulosic matrix and a polymer of intrinsic microporosity (PIM). The PIM includes chains coupled by a heat-treating under vacuum.

A method for forming an isoporous graded film comprising multiblock copolymers and isoporous graded films. The films have a surface layer and a bulk layer. The surface layer can have at least 1×10.sup.14 pores/m.sup.2 and a pore size distribution (d.sub.max/d.sub.min)) of less than 3. The bulk layer has an asymmetric structure. The films can be used in filtration applications.

A virus removal membrane includes cellulose, and a primary-side surface through which the protein-containing solution is to be applied and a secondary-side surface from which a permeate that has permeated the virus removal membrane is to be flowed, wherein a bubble point is 0.5 MPa or more and 1.0 MPa or less; and when a solution containing gold colloids having a diameter of 30 nm is applied through the primary-side surface to the virus removal membrane to allow the virus removal membrane to capture the gold colloids for measurement of brightness in a cross section of the virus removal membrane, a value obtained by dividing a standard deviation of a value of an area of a spectrum of variation in the brightness by an average of the value of the area of the spectrum of variation in the brightness is 0.01 or more and 0.30 or less.

A hollow fiber membrane of the present invention is a hollow fiber membrane having an outer surface and an inner surface, wherein the inner surface has a zebra stripe pattern in which dense portions and porous portions are alternately formed in the longitudinal direction, and the outer surface has a maximum pore size of about 1 μm or less (≤about 1 μm), and wherein the hollow fiber membrane has a water permeability (flux) of ≥about 1,300 LMH/bar to ≤about 5,000 LMH/bar.

A gas separation membrane, methods of forming the membrane, and methods of using the membrane for gas separation are provided. An exemplary gas separation membrane includes a cellulosic matrix and a polymer of intrinsic microporosity (PIM). The PIM includes chains coupled by a heat-treating under vacuum.