A porous membrane includes a polymer which includes one or more structural units selected from the group consisting of a structural unit represented by Formula (I) and a structural unit represented by Formula (II), in which a content of the structural unit represented by Formula (II) is 1% by mass or more and less than 10% by mass with respect to a total mass of the structural unit represented by Formula (I) and the structural unit represented by Formula (II)

##STR00001##

Provided is a method for preparing a gas separation membrane, the method including forming a porous layer by coating a hydrophilic polymer solution on a porous substrate; and forming an active layer by coating a composition for forming an active layer including a polymer of Chemical Formula 1 on the porous layer,

##STR00001## wherein in Chemical Formula 1, n is the number of a repeating unit, and is an integer of 500 to 3,000, and R1 to R5 are the same as or different from each other, and each independently is hydrogen, an alkyl group, or (CO)R6, and R6 is an alkyl group, wherein the polymer of Chemical Formula 1 is included in an amount from 1% by weight to 5% by weight based on the composition for forming an active layer, and a gas separation membrane prepared using the same.

Provided is a method for preparing a gas separation membrane, the method including forming a porous layer by coating a hydrophilic polymer solution on a porous substrate; and forming an active layer by coating a composition for forming an active layer including a polymer of Chemical Formula 1 on the porous layer,

##STR00001## wherein in Chemical Formula 1, n is the number of a repeating unit, and is an integer of 500 to 3,000, and R1 to R5 are the same as or different from each other, and each independently is hydrogen, an alkyl group, or (CO)R6, and R6 is an alkyl group, wherein the polymer of Chemical Formula 1 is included in an amount from 1% by weight to 5% by weight based on the composition for forming an active layer, and a gas separation membrane prepared using the same.

According to the method and device for a membrane-based processing of ambient water-group species, the species are captured in a space environment by an ionic liquid disposed on a presenting face of a semipermeable membrane. To seamlessly process the captured species for in-situ resource utilization without need of moving parts, they are urged to pass through the membrane by a predetermined electric potential difference applied between opposite sides of the membrane via electrode contacts; an initial storage envelope is provided by an impermeable membrane attached to a back face of the semipermeable membrane. The device can be stowed in a manner of rolled plastic and deployed by unrolling. The device can also be configured as a scientific instrument to monitor a flux of ambient water-group species impinging in the space environment using electrical measurements.

According to the method and device for a membrane-based processing of ambient water-group species, the species are captured in a space environment by an ionic liquid disposed on a presenting face of a semipermeable membrane. To seamlessly process the captured species for in-situ resource utilization without need of moving parts, they are urged to pass through the membrane by a predetermined electric potential difference applied between opposite sides of the membrane via electrode contacts; an initial storage envelope is provided by an impermeable membrane attached to a back face of the semipermeable membrane. The device can be stowed in a manner of rolled plastic and deployed by unrolling. The device can also be configured as a scientific instrument to monitor a flux of ambient water-group species impinging in the space environment using electrical measurements.

A process is provided of making facilitated transport membrane comprising a relatively hydrophilic, very small pore, nanoporous support membrane, a hydrophilic polymer inside the very small nanopores on the skin layer surface of the support membrane, a thin, nonporous, hydrophilic polymer layer coated on the surface of the support membrane, and metal salts incorporated in the hydrophilic polymer layer coated on the surface of the support membrane and the hydrophilic polymer inside the very small nanopores. In addition, the process provides a new method of making facilitated transport membrane spiral wound elements or hollow fiber modules for olefin/paraffin separations, particularly for C3=/C3 and C2=/C2 separations.

A process is provided of making facilitated transport membrane comprising a relatively hydrophilic, very small pore, nanoporous support membrane, a hydrophilic polymer inside the very small nanopores on the skin layer surface of the support membrane, a thin, nonporous, hydrophilic polymer layer coated on the surface of the support membrane, and metal salts incorporated in the hydrophilic polymer layer coated on the surface of the support membrane and the hydrophilic polymer inside the very small nanopores. In addition, the process provides a new method of making facilitated transport membrane spiral wound elements or hollow fiber modules for olefin/paraffin separations, particularly for C3=/C3 and C2=/C2 separations.

A gas detector comprises a gas detection unit and a filter introducing surrounding atmosphere to the gas detection unit. The filter comprises a gas-permeable organic polymer membrane having an acidic group or a basic group.

A gas detector comprises a gas detection unit and a filter introducing surrounding atmosphere to the gas detection unit. The filter comprises a gas-permeable organic polymer membrane having an acidic group or a basic group.

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.