The invention relates to a specific process and apparatus for separation of gas mixtures with reduced maintenance costs.

Porous liquid-filtering membranes are provided having a boundary region substantially surrounding the pore region and having greater tear resistance than the pore region.

Various embodiments of a system and method for enriching a concentration of components of interest in an air flow are described. The system includes an apparatus for enriching a concentration of components of interest in an air flow. The apparatus includes a chamber and a tube having a tube wall made of a selectively permeable material positioned within the chamber. A first end of the tube is connected to the inlet port of the chamber and a second end of the tube is connected to the outlet port of the chamber. The selectively permeable material has a lower permeability to components of interest than to inert gases, and the selectively permeable material is non-reactive with components of interest. The apparatus is configured to receive a sample stream and the chamber is maintained at a chamber pressure that is different than a stream pressure of the sample stream.

A polymer composite membrane, a method for fabricating same, and a lithium-ion battery including same are provided. The polymer composite membrane includes a porous base membrane and a heat-resistant layer covering at least one side surface of the porous base membrane, the heat-resistant layer includes a plurality of heat-resistant sub-layers sequentially stacked, and pore-blocking temperatures of the heat-resistant sub-layers are sequentially increased from inside to outside; each of the heat-resistant sub-layers includes at least one of a first heat-resistant polymer material and a second heat-resistant polymer material, and each of the heat-resistant sub-layers is separately configured as a fiber network structure; the melting point of the first heat-resistant polymer material is not less than 200 C.; and the melting point of the second heat-resistant polymer material is not less than 100 C.

This invention discloses a membrane composition, a method of making, and applications for a new type of high selectivity, high plasticization-resistant and solvent-resistant, both chemically and UV cross-linked polyimide membranes. Gas permeation tests on these membranes demonstrated that they not only showed high selectivities, but also showed extremely high CO.sub.2 plasticization resistance under CO.sub.2 pressure up to 4923 kPa (700 psig). This new type of high selectivity, high plasticization-resistant and solvent-resistant, both chemically and UV cross-linked polyimide membranes can be used for a wide range of gas separations such as separations of H.sub.2/CH.sub.4, He/CH.sub.4, CO.sub.2/CH.sub.4, CO.sub.2/N.sub.2, olefin/paraffin separations (e.g. propylene/propane separation), O.sub.2/N.sub.2, iso/normal paraffins, polar molecules such as H.sub.2O, H.sub.2S, and NH.sub.3 mixtures with CH.sub.4, N.sub.2, H.sub.2, and other light gases separations. The membranes can also be used for liquid separations such as in the removal of organic compounds from water.

A composite membrane comprising: (a) a porous support; (b) optionally a gutter layer; (c) a polyimide discriminating layer; and (d) a protective layer comprising dialkylsiloxane groups and having an average thickness of 825 to 2,000 nm; wherein the polyimide discriminating layer comprises 2,4,6-trimethyl-1,3-phenylene groups, each such group independently having an atom or substituent other than H at the 5-position.

The disclosure provides for polymer membranes which comprise metal organic frameworks, methods of making therein, and methods of use thereof, including in gas separation.

A process for producing nitrogen-rich air by feeding high temperature air at 150 C. or more to an air separation membrane module is described. After being placed at 175 C. for two hours, the air separation module exhibits a shape-retention ratio of 95% or more in one embodiment. The nitrogen-rich air can be fed to a fuel tank for an aircraft, for example.

Disclosed herein is a double-layer ion-selective membrane, method of production, applications of the double-layer ion-selective membrane as a redox flow cell, a fuel cell, and used for wastewater and air purification. The double-layer ion-selective membrane is comprised of a polyetherimide (PEI) layer and an ultrathin layer comprising porous boron nitride (PBN) flakes enmeshed by a NAFION? resin. The double layer membrane exhibits ion-selectivity and ion-conductivity enabling the membrane to be used in a redox flow cell battery, a fuel cell battery, and to be used in wastewater and air purification applications.

A process for producing nitrogen-rich air by feeding high temperature air at 150 C. or more to an air separation membrane module is described. After being placed at 175 C. for two hours, the air separation module exhibits a shape-retention ratio of 95% or more in one embodiment. The nitrogen-rich air can be fed to a fuel tank for an aircraft, for example.