The forward osmosis membrane and the preparation method thereof provided by the present invention, through fully cover the support mesh layer of the membrane with antibacterial nanoparticles, especially the mixture of nano-Ag and nano TiO2, ensures without reducing the strength, water flux and salt rejection, providing an effective, long-term and comprehensive antibacterial effect. In the present invention, the antibacterial nanoparticles, especially the mixture of nano-Ag and nano-TiO2, are used to carry out antibacterial modification on the support mesh of the forward osmosis membrane, so as to inhibit the growth of bacteria on the forward osmosis membrane, improves the forward osmosis and also improves the safety of the entire purification and filtration system. The antibacterial forward osmosis membrane of the present invention can be applied to the filtration and purification of complex water sources, especially the purification and filtration of eutrophic and bacteria-prone water sources.

Membranes, methods of making the membranes, and methods of using the membranes are described herein. The membranes can comprise a gas permeable support layer, an inorganic layer disposed on the support, the inorganic layer comprising a plurality of discreet nanoparticles having an average particle size of less than 1 micron, and a selective polymer layer disposed on the inorganic layer, the selective polymer layer comprising a selective polymer having a CO.sub.2:N.sub.2 selectivity of at least 10 at 57° C. In some embodiments, the membrane can be selectively permeable to an acidic gas. The membranes can be used, for example, to separate gaseous mixtures, such as flue gas.

Methods herein disclosed include methods of producing a nanoporous membrane by coating a planar substrate (204) with a solution (solution tank 201) containing a reactive metal adatom. The coated planar substrate can then be perforated by initiating a redox reaction between the reactive metal adatom and the planar substrate that causes the reactive metal adatom to remove material, forming nanoscale pores in the planar substrate that result in a nanoporous planar material. This nanoporous planar material can be formed into a nanoporous membrane.

A carbon molecular sieve (CMS) membrane having improved separation characteristics for separating olefins from their corresponding paraffins is comprised of carbon with at most trace amounts of sulfur and a group 13 metal. The CMS membrane may be made by pyrolyzing a precursor polymer devoid of sulfur in which the precursor polymer has had a group 13 metal incorporated into it, wherein the metal is in a reduced state. The pyrolyzing for the precursor having the group 13 metal incorporated into it is performed in a nonoxidizing atmosphere and at a heating rate and temperature such that the metal in a reduced state (e.g., covalently bonded to carbon or nitrogen or in the metal state).

A gas separation membrane selectively permeable to a specific gas component includes a first porous layer, and a separation function layer provided on a first surface of the first porous layer. The separation function layer contains a hydrophilic resin. The first surface has a wetting tension of greater than or equal to 38 mN/m and less than or equal to 52 mN/m.

A method for making a filter membrane includes: forming a polymer layer; applying a plurality of nanoparticles on the polymer layer, the nanoparticles being self-assembled to form a closed pack arrangement on the polymer layer; heating the nanoparticles such that a portion of the polymer layer contacting the nanoparticles is softened so that the nanoparticles are sunk into the polymer layer; and removing the nanoparticles from the polymer layer so that the polymer layer is formed with a plurality of pores penetrating the polymer layer and being arranged in a honeycomb pattern.

The present invention provides an intrinsically anti-microbial hollow fiber membrane for filtration of liquids. The membrane comprises a plurality of porous hollow bilayer membrane fibers wherein the liquid enters from outside of the fiber, passing through the porous membrane into the lumen of the fiber and coming out from the hollow ending of the fiber, wherein this configuration provides a liquid outside-in arrangement and retains the filtrate outside. It means that membrane of the invention has built in characteristics to act against microbes in order to provide the use with a safe liquid free from microbes. The outer side or outer wall of the hollow fibers may be configured to become hydrophobic whereas inner side or inner wall of the hollow fiber membrane may be configured to become hydrophilic to enhance the water permeability to a great extent. The hollow fiber membrane may be configured to give it an intrinsic anti-microbial capability. A device containing above said membrane has also been disclosed.

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.

The present invention provides an intrinsically anti-microbial hollow fiber membrane for filtration of liquids. The membrane comprises a plurality of porous hollow bilayer membrane fibers wherein the liquid enters from outside of the fiber, passing through the porous membrane into the lumen of the fiber and coming out from the hollow ending of the fiber, wherein this configuration provides a liquid outside-in arrangement and retains the filtrate outside. It means that membrane of the invention has built in characteristics to act against microbes in order to provide the use with a safe liquid free from microbes. The outer side or outer wall of the hollow fibers may be configured to become hydrophobic whereas inner side or inner wall of the hollow fiber membrane may be configured to become hydrophilic to enhance the water permeability to a great extent. The hollow fiber membrane may be configured to give it an intrinsic anti-microbial capability. A device containing above said membrane has also been disclosed.

Provided is a gas separation membrane containing polysaccharides and being characterized by having a crystallinity of 17% or lower, the crystallinity being represented by equation (1) below: (1) Crystallinity (%)=[I.sub.c/(I.sub.c+I.sub.a)]100 (In equation (1), I.sub.c is the sum of the integrals of the scattering intensities of crystalline peaks obtained from X-ray diffraction analysis of the gas separation membrane, and I.sub.a is the sum of the integrals of the scattering intensities of the amorphous halo).