Abstract: A method of forming a fluid separation filter for use in a fluid separation device includes aligning a series of fluid separation or drying fibers (102) and fixing them together using a self-adhesive and electrically conductive tape (116) or by weaving copper threads between them. The connected fibers then form a mat and a strip of potting sealant (112) may be added, if required, along the top and bottom of the fibers. The mat may then be rolled to form a bundle of fibers.

Abstract: The invention describes a polymeric material comprising repeating units of Formulae I-III and methods of preparation. Novel polymeric materials, gas separation membranes and fluid component separation methods are also described.

Abstract: A composite hollow ceramic fiber includes a porous hollow core supporting a thin, dense sheath. The non-gas-tight core comprises a first ceramic compound and an interconnecting network of pores. The gas-tight sheath comprises a second ceramic compound. The fiber is made by extruding first and second suspensions of the first and second ceramic compounds in polymeric binders and solvent from a spinnerette and coagulating the nascent hollow fiber to effect phase inversion of the polymeric binders. The resultant green fiber is sintered in a two step process. First, the binder is burned off. Second, the sheath is densified and the second ceramic compound is sinter without fully sintering the first ceramic compound. The first ceramic compound has a melting point higher than that of the second ceramic compound.

Abstract: A composite hollow ceramic fiber includes a porous hollow core supporting a thin, dense sheath. The non-gas-tight core comprises a first ceramic material and an interconnecting network of pores. The gas-tight sheath comprises a second ceramic material. The fiber is made by extruding core and sheath suspensions from a spinnerette. The core suspension includes particles of the first ceramic material, a polymeric binder, a solvent, and a pore former material insoluble in the solvent. The sheath suspension includes particles of the second ceramic material, a polymeric binder and a solvent. The nascent hollow fiber is coagulated in a coagulant bath to effect phase inversion of the polymeric binders. The resultant green fiber is sintered in a two step process. First, the binders and pore former material are burned off. Second, the sheath is densified and the second ceramic material is sintered without fully sintering the core.

Abstract: The present invention relates to an asymmetric hollow fiber membrane for gas separation made of a soluble aromatic polyimide, wherein an orientation index is 1.3 or less, a separation coefficient ?(P?O2/P?N2) as a permeation rate ratio of oxygen gas/nitrogen gas at 40° C. is 5.3 or more, and a tensile fracture elongation is 15% or more.

Abstract: Disclosed herein is a method for preparing a crosslinked hollow fiber membrane. The method involves spinning a one phase solution comprising a monoesterified polyimide polymer, acetone as a volatile solvent, a spinning solvent, a spinning non-solvent, and optionally an organic and/or inorganic additive, wherein the volatile solvent is present in an amount of greater than 25 wt. % to about 50 wt. %, based on the total weight of the solution.

Abstract: The inventive stage system for producing hydrogen consists of at least two upstream/downstream stages, respectively, each of which comprises, optionally, a catalytic reactor (C1 to C5) followed by a separator comprising a space (E1 to E4) for circulation of a gaseous mixture contacting at least one oxygen extracting membrane and a hydrogen collecting space, wherein the reactor (C1) of the upstream stage is connected to a reaction gaseous mixture source, the circulation stage (E1) of the upstream stage separator is connected to the reactor (C2) of the downstream stage and the spaces for extracting/collecting oxygen from two separators are connected to a hydrogen collecting circuit (TC, 8) which is common for two stages.

Abstract: The invention concerns carbon molecular sieve membranes (“CMS membranes”), and more particularly the use of such membranes in gas separation. In particular, the present disclosure concerns an advantageous method for producing CMS membranes with desired selectivity and permeability properties. By controlling and selecting the oxygen concentration in the pyrolysis atmosphere used to produce CMS membranes, membrane selectivity and permeability can be adjusted. Additionally, oxygen concentration can be used in conjunction with pyrolysis temperature to further produce tuned or optimized CMS membranes.

Abstract: In some implementations, a system for disassociating water includes a decomposition chamber, a heating element, a plurality of hollow fiber membranes, and a water inlet. The heating element is positioned in the decomposition chamber and configured to generate heat sufficient to dissociate at least a portion of water to hydrogen and oxygen. The plurality of hollow fiber membranes include at least a section of each hollow fiber membrane that passes through the decomposition chamber and has an inner conduit and an outer wall. The inner conduit for each hollow fiber membrane is configured to pass a sweep gas, and the outer wall for each hollow fiber membrane is configured to selectively pass either oxygen or hydrogen. The water inlet connected to the decomposition chamber and configured to pass water vapor into the decomposition chamber.

Abstract: A process for producing a zeolite film is provided in which seed crystals thinly adhere to the surface of a support to form a thin and even zeolite film having fewer defects than conventional zeolite films. Also provided is a zeolite film obtained by the producing process. The process for producing the zeolite film comprises: a particle adhesion step of allowing a slurry, where zeolite particles which become seeds are dispersed, to flow down on the surface of a base material by the self-weight of the slurry, so that the zeolite particles adhere to the base material; and a film formation step of immersing the base material, to which the zeolite particles adhere, into a sol to carry out hydrothermal synthesis, thereby forming the zeolite film on the base material.

Abstract: In at least certain embodiments, the present invention is directed to contactors, modules, components, systems, and/or methods of manufacture, and/or methods of use including degassing liquids. In at least particular possibly preferred embodiments, the contactor or module is integrally potted, has planar, disc shaped end caps, and a cylindrical housing or shell receiving and supporting a membrane structure. In at least particular possibly preferred embodiments, each of the planar disc shaped end caps has a central opening therein adapted to receive a liquid end port or nozzle, another opening therein adapted to receive a gas end port or threaded pipe, and is held in place in the housing or shell by at least one retaining element such as a retaining or locking ring. In at least particular possibly preferred embodiments, the integrally potted membrane structure is potted in place in the housing or shell by an inverted potting process involving the use of a removable plunger or plug to recess the potting.

Abstract: A liquid degassing apparatus is arranged to prevent pervaporated solvent cross-contamination by counteracting liquid vapor pervaporation flow. Liquid vapor pervaporation cross-contamination among a plurality of degassing modules is counteracted with specifically configured volumes and bleed inlet flow to conduits fluidly coupling permeate sides of said plurality of degassing chambers.

Abstract: The present invention is directed toward spiral wound modules along with methods for making and using the same. Several embodiments are described including methods for making spiral wound filtration modules using membrane sheet provided from a roll, wherein the membrane sheet is unrolled and assembled in a direction parallel to the permeate collection tube of the module.

Abstract: A hybrid multichannel porous structure for processing between two fluid streams of different compositions includes a housing and one or more structures disposed within the cavity of the housing in a shell and tube configuration. Each structure includes a body made of a porous, inorganic material and a plurality of channels for processing an optional sweep stream. Each channel is coated with a membrane layer. A feed stream introduced into the housing is in direct contact with the structures such that a gas selectively permeates through the body and into the channels. The gas combines with the sweep stream to form a permeate that exits from each channel. The remaining feed stream forms a retentate that exits from the housing. The feed stream may consist of syngas containing hydrogen gas and the sweep stream may contain nitrogen gas. A power plant that incorporates the hybrid structure is disclosed.

Abstract: A shell-and-tube heat exchanger, for removing volatile substances from a polymer solution by degasification, includes a bundle of tubes arranged vertically and parallel to each other in a shell chamber through which a fluid heat-transfer medium flows. The upper end of each tube is fixed in an upper tube sheet and the lower end of each tube is fixed in a lower tube sheet, and the polymer solution flows through the tubes in the direction of gravity. One feature is that a multilayer woven wire fabric is attached to the top of the upper tube sheet. The finest meshed layer of the fabric has a mesh width of 50 ?m to 1000 ?m. The invention also relates to a method for removing volatile substances from a polymer solution by degasification in a shell-and-tube heat exchanger and use of the shell-and-tube heat exchanger.

Abstract: A gas separation membrane module, comprising: a hollow fiber element having a hollow fiber bundle consisting of a number of hollow fiber membranes and a tube sheet provided at an end of the hollow fiber bundle for binding the hollow fiber membranes; a vessel having an opening through which the hollow fiber element is inserted or removed; a lid member having a gas outlet formed therein and attached to cover the opening of the vessel; and a perforated plate having a plurality of through holes for forming gas channels formed therein, the perforated plate being mounted between the tube sheet and the lid member, the gas separation membrane module performing gas separation by supplying mixed gas to the hollow fiber membranes.

Abstract: Hollow fiber membranes, such as those used in air separation modules, are generally made from solution spinning. Typically, solvent is present in the bore of the fiber for the spinning process. This solvent, in addition to the solvent already present in the polymer casting solution, may cause voids in the fiber material. By adding a polycarboxylic acid to the polymer casting material, these voids may be reduced or eliminated.

Abstract: A composition includes a first polymer having monomers each containing an imidazole group, and a second polymer, the first and second polymers being a polymer blend. The first polymer, the second polymer, or both may be cross-linked. The carbonized composition, polymeric and carbon membranes (either in the form of a flat sheet or a hollow fiber) made from the composition are also described. The polymeric and carbon membranes can be used to separate and purify gases or liquids.

Abstract: Nanocomposite adsorbent materials and methods for their preparation and use are described. As an example, a polyaniline-graphite nanoplatelet nanocomposite may be used to adsorb carbon dioxide.

Abstract: The various embodiments of the disclosure relate generally to carbon molecular sieve membranes (CMSM) and their associated fabrication processes, and more particularly to CMSM that maintain high gas selectivities without losing productivity. Methods for enriching a mixture of gases in one gas via the use of the CMS membranes, and gas enrichment devices using the same, are also disclosed.

Abstract: A porous membrane structure is disclosed, which includes a porous substrate, a mesoporous, aluminum oxide layer disposed on the substrate; and a relatively thin, continuous, microporous barrier layer disposed on the mesoporous aluminum oxide layer, also formed from aluminum oxide. The membrane is capable of improving hydrogen selectivity within a gas stream, e.g., a synthesis gas composition. Membrane supports containing these structures are also described, as well as gas separation modules, and related processes. Power plants which incorporate the gas separation modules are also disclosed herein.

Abstract: An asymmetric hollow fiber gas separation membrane obtained by subjecting an asymmetric hollow fiber polyimide membrane to a heat treatment having a maximum temperature of from 350 to 450° C., wherein the asymmetric hollow fiber polyimide membrane is formed with a polyimide essentially having a repeating unit represented by a general formula (1); is excellent in a solvent resistance and a thermal stability, and as well has such a mechanical strength that a tensile elongation at break is not less than 10% as a hollow fiber membrane.

Abstract: Method and apparatus for a membrane separation system, including process and installation for the separation of air by permeation, using two strategically placed heaters for the production of high purity nitrogen, uniquely designed multi-staged pre-filtration system and a novel method of controlling the nitrogen flow and purity. The system comprises in series an air compressor (1), an air cooler (2) cooled by air or liquid, moisture separator (3), mist removing filter (4), primary heat source (5), coalescing filter (8), carbon tower (9), particle filter (10), secondary heat source (11), membrane separator(s) (14), and control valve (19). The system is to provide and maintain superheated air to the membrane separator(s) using strategically located heaters to eliminate condensation of moisture in the carbon tower or membrane separator(s) eliminating the need for a separate compressed air dryer, or the need for insulation of pipes, vessels and the membrane separator(s).

Abstract: A gas separation device comprising a porous support structure comprising polymeric hollow fibers, and an inorganic mesoporous membrane disposed on the porous support structure is disclosed. The inorganic mesoporous membrane is uniform and free of defects. Further, the inorganic mesoporous membrane comprises a network of interconnected three-dimensional pores that interconnect with the porous support structure. The gas permeances of the inorganic mesoporous membrane is substantially higher than the gas permeances of the polymeric hollow fibers. A method of fabricating the gas separation device is also disclosed.

Abstract: The invention relates to a device for preparing a gas flow for introduction thereof into a mass spectrometer, wherein the gas flow contains one or more analytes and has helium as carrier gas. According to the invention, a selective separating device is provided for separating off a part of the carrier gas from the gas flow (10), to form a residual gas flow (11) and a separated carrier gas flow (12). A higher fraction of the analyte is present therein than in the gas flow and in the separated carrier gas flow there is a lower fraction of the analyte.

Abstract: An apparatus for capture and sequestration of CO2 from fossil fuel-fired power plant flue gas includes a polymer matrix embedded with a sorbent suitable for removing CO2 from the flue gas and a spacer mated with the polymer matrix. The spacer is adapted to create channels between adjacent portions of the polymer matrix such that the flue gas flows through the channels and comes in contact with the sorbent. Further, an apparatus for the capture and sequestration of CO2 from fossil fuel-fired power plant flue gas includes a hollow fiber membrane embedded with an adsorbent or other suitable material for removing CO2 from the flue gas. The adsorbent particles may be embedded into a wall of the membrane.

Abstract: A method is proposed for operating a plant for purifying a high-pressure gas mixture from easily permeating components, which plant comprises membrane gas separating units having a high-pressure chamber and a low-pressure chamber with a selectively permeable membrane therebetween, in which method the low-pressure chamber of at least one membrane gas separating unit is continuously flushed with purified gas mixture (semi-finished product or product), wherein the pressure difference between the aforementioned chambers of the membrane gas separating unit and, likewise, the flow rate of the purified gas mixture used for flushing are maintained so that the amount of each easily permeating component in the product does not exceed the desired values. The proposed method makes it possible to purify a raw material from one or more easily permeating components simultaneously, increase purification efficiency, and provide the possibility of using raw material with a higher content of easily permeating components.

Abstract: There is provided herein a dryer polymer substance including a hetero-phase polymer composition including two or more polymers wherein at least one of the two or more polymers include sulfonic groups, wherein the substance is adapted to pervaporate a fluid. The fluid may include water, water vapor or both. There is also provided herein a process for the preparation of a dryer polymer substance adapted to pervaporate a fluid (such as water, water vapor or both) the process includes mixing two or more polymers, wherein at least one of the two or more polymers may include groups which are adapted to be sulfonated, to produce a hetero-phase polymer composition and processing the polymer blend into a desired form.

Abstract: A blood storage system. The system has a collection bag for red blood cells; an oxygen/carbon dioxide depletion device; a storage bag for red blood cells; and tubing connecting the collection bag to the depletion device and the depletion device to the storage bag. The depletion device includes a receptacle of a solid material having an inlet and an outlet adapted to receiving and expelling a flushing gas; a plurality of hollow fibers or gas-permeable films extending within the receptacle from an entrance to an exit thereof. The hollow fibers or gas-permeable films are adapted to receiving and conveying red blood cells.

Abstract: A separation membrane module for separating a specific component from a mixture containing a plurality of components includes a plurality of separation stages each including a plurality of hollow fiber membranes arranged in parallel to each other. The separation stages are connected in series via connection portions allowing passage of the mixture. At lease one parameter relating to separation by the hollow fiber membrane or membranes in each separation stage is determined to provide effective separation throughout the separation stages.

Abstract: A module and an apparatus incorporating such module utilizing a plurality of tubular membrane elements, each configured to separate oxygen from an oxygen containing feed stream when an electric potential difference is applied to induce oxygen ion transport in an electrolyte thereof. The tubular membrane elements can be arranged in a bundle that is held in place by end insulating members. The insulating members can be positioned within opposed openings of end walls of a heated enclosure and can incorporate bores to allow an oxygen containing feed stream to flow past exposed ends of the tubular membrane elements for cooling the end seals of such elements. Further, first and second manifolds can be provided in a module in accordance with the present invention to collect separated oxygen from two separate portions of the tubular membrane elements.

Abstract: Methods for the purification of steam, systems for purifying steam, methods for measuring and/or controlling steam flow rates, and uses for purified steam are provide. Also provided are substantially gas-impermeable membranes, such as perfluorinated ionomers (e.g., perfluoroethylene-sulfonic-acid/tetrafluoroethylene membranes), having a high ratio of water vapor permeation relative to gas permeation through the membrane. Also provided are methods of operation of such membranes at relatively high operating temperatures for the purification of steam and for operation of such membranes at relatively low temperature and sub-atmospheric pressures for the purification of steam. In a preferred embodiment, the system 400 for purifying steam comprises heater 404 for creating a source of a steam feed, and a purification device 416 for housing a substantially gas-impermeable membrane 424. In the operation of system 400, water, such as deionized water, is added to vessel 402 to provide a source of the steam feed.

Abstract: A tubesheet, modules incorporating tubesheets and methods for making and using the same. In one embodiment the invention includes a tubesheet comprising: i) a plurality of aligned semi-permeable hollow fiber membranes each comprising a cylindrical porous structure surrounding a lumen and extending between a first and second end and further comprising a first segment located adjacent the first end and a second segment located adjacent to the second end and ii) a block of potting material including an interfacial surface. The first segment of the hollow fiber membrane is embedded within the block of potting material and the second segment extends from the interfacial surface of the block. The tubesheet further comprises a penetrating extension of potting material within the porous structure of the second segment of the hollow fiber membrane that extends along a length from the interfacial surface of the block to a distal end.

Abstract: In accordance with at least selected embodiments of the present invention, an improved liquid degassing membrane contactor or module includes a high pressure housing and at least one degassing cartridge therein. It may be preferred that the high pressure housing is a standard, ASME certified, reverse osmosis (RO) or water purification pressure housing or vessel (made of, for example, polypropylene, polycarbonate, stainless steel, corrosion resistant filament wound fiberglass reinforced epoxy tubing, with pressure ratings of, for example, 150, 250, 300, 400, or 600 psi, and with, for example 4 or 6 ports, and an end cap at each end) and that the degassing cartridge is a self-contained, hollow-fiber membrane cartridge adapted to fit in the RO high pressure housing.

Abstract: A water vapor permeable membrane is provided comprising a dense layer and a support layer that are adjacent to each other, wherein the dense layer contains voids with a void length of 0.1 ?m or less and the dense layer has a thickness of 0.1 ?m or more and 2 ?m or less while in the support layer, void (a), i.e. the void with the largest length in the 2 ?m thick region measured from the boundary between the dense layer and the support layer into the support layer, has a length of 0.3 ?m or more and void (b), i.e. the void with the largest length in the region ranging between 2 ?m and 4 ?m measured from the boundary into the support layer, has a length of 0.5 ?m or more, the length of the void (b) being larger than that of the void (a). A water vapor permeable membrane having both a high water vapor permeability and a low air leakage is provided.

Abstract: The invention provides a porous nanoscale membrane. In one embodiment, the membrane can be used as a filtration device to screen agents that disrupt or prevent molecular interactions. In one embodiment, the membrane allows for screening agents that disrupt or prevent molecular interactions using a small sample volume with efficient high-throughput screening applications.

Abstract: The invention concerns carbon molecular sieve membranes (“CMS membranes”), and more particularly the use of such membranes in gas separation. In particular, the present disclosure concerns an advantageous method for producing CMS membranes with desired selectivity and permeability properties. By controlling and selecting the oxygen concentration in the pyrolysis atmosphere used to produce CMS membranes, membrane selectivity and permeability can be adjusted. Additionally, oxygen concentration can be used in conjunction with pyrolysis temperature to further produce tuned or optimized CMS membranes.

Abstract: A hybrid multichannel porous structure for processing between two fluid streams of different compositions includes a housing and one or more structures disposed within the cavity of the housing in a shell and tube configuration. Each structure includes a body made of a porous, inorganic material and a plurality of channels for processing an optional sweep stream. Each channel is coated with a membrane layer. A feed stream introduced into the housing is in direct contact with the structures such that a gas selectively permeates through the body and into the channels. The gas combines with the sweep stream to form a permeate that exits from each channel. The remaining feed stream forms a retentate that exits from the housing. The feed stream may consist of syngas containing hydrogen gas and the sweep stream may contain nitrogen gas. A power plant that incorporates the hybrid structure is disclosed.

Abstract: A high-pressure capillary degas assembly includes an assembly block having an eluent inlet and an eluent outlet, and a separator support extending therebetween, a wash inlet and a wash outlet and a groove extending therebetween, a tubular separator extending within the assembly block, the separator having an inner surface and an outer surface, the inner surface defining an eluent fluid line fluidly interconnecting the eluent inlet and outlet, the outer surface abutting against the separator support and enclosing the groove to define a wash line within the groove. The separator may be configured to retain liquid in the eluent fluid line at a first pressure and allow gas to flow through the separator to the wash fluid line at a second pressure lower than the first pressure. A method of using the high-pressure capillary degas assembly is also disclosed.

Abstract: The present invention is directed to contactors, modules, components, systems, and/or methods of manufacture, and/or methods of use including degassing liquids. The contactor or module is integrally potted, has planar, disc shaped end caps, and a cylindrical housing or shell receiving and supporting a membrane structure. Each of the planar disc shaped end caps has a central opening therein adapted to receive a liquid end port or nozzle and is held in place in the housing or shell by at least one retaining element. The integrally potted membrane structure is preferably potted in place in the housing or shell by an inverted potting process involving the use of a removable plunger or plug to recess the potting.

Abstract: Disclosed herein is a method for preparing a crosslinked hollow fiber membrane. The method involves spinning a one phase solution comprising a monoesterified polyimide polymer, acetone as a volatile solvent, a spinning solvent, a spinning non-solvent, and optionally an organic and/or inorganic additive, wherein the volatile solvent is present in an amount of greater than 25 wt. % to about 50 wt. %, based on the total weight of the solution.

Abstract: A module and an apparatus incorporating such module utilizing a plurality of tubular membrane elements, each configured to separate oxygen from an oxygen containing feed stream when an electric potential difference is applied to induce oxygen ion transport in an electrolyte thereof. The tubular membrane elements can be arranged in a bundle that is held in place by end insulating members. The insulating members can be positioned within opposed openings of end walls of a heated enclosure and can incorporate bores to allow an oxygen containing feed stream to flow past exposed ends of the tubular membrane elements for cooling the end seals of such elements. Further, first and second manifolds can be provided in a module in accordance with the present invention to collect separated oxygen from two separate portions of the tubular membrane elements.

Abstract: A liquid degassing apparatus is arranged to limit pervaporation through a membrane by establishing a pervaporation control space at a permeate side of the membrane. The pervaporation control space is defined in a vacuum chamber between the membrane and a shield member. The shield member may be substantially gas and liquid impermeable to maintain an environment in contact with the permeate side of the membrane that is relatively rich in solvent vapor concentration, thereby limiting further liquid pervaporation across the membrane.

Abstract: An apparatus and method for enhancing the heat and water recovery from a transport membrane condenser (TMC) includes a non-moving mechanical device inserted into the TMC tubes to increase the heat transfer efficiency via the enhancement of the fluid turbulence and/or surface area. The apparatus and methods may be applied to porous tubes arranged in a spaced array, similar to a conventional shell and tube heat exchanger device. Other configurations of the TMC may be conceived and adapted for use with the described apparatus and method.

Abstract: A degas assembly including a low pressure fluid channel for carrying a wash fluid at a first pressure, a pressurized channel for carrying eluent including a gas at a second pressure higher than the first pressure, and a degas separator defining a fluid barrier between the low pressure fluid channel and pressurized fluid channel, the separator configured to retain liquid in the pressurized fluid channel and allow gas to flow through the separator to the low pressure fluid channel. The pressurized fluid channel may extend along an outer periphery of the low pressure fluid channel. The eluent may be received from an eluent generator at a pressure of at least about 3300 psi, and in various embodiments up to about 5000 psi. A liquid chromatography system and method are also disclosed.

Abstract: To provide a humidifying membrane module that is reduced in weight, size and cost by making a case in a single layer structure, the humidifying membrane module has a hollow fiber membrane bundle constructed from plural hollow fiber membranes, a case accommodating the hollow fiber membrane bundle, a first flow passage extending through hollows of the hollow fiber membranes, and a second flow passage extending through the outer surface sides of the hollow fiber membranes, the membrane bundle and the case are simultaneously integrated at both ends of the membrane bundle by using potting members sealing gaps between the membrane bundle and the case, an inlet and an outlet constructing the first flow passage are formed at the both ends of the case respectively, and an entrance and an exit constructing the second flow passage are formed in side surfaces near the both ends of the case respectively.

Abstract: The present invention is directed to degassing devices for dialysate circuits. One embodiment has a first housing and a second housing positioned within the first housing in an annular relationship. A second embodiment comprises a dialysate regeneration system with urease, a dialyzer, and a housing with an external wall, where the external wall is exposed to atmosphere and comprises a material that passes gas but does not pass liquid and where the housing is positioned between the urease and dialyzer.

Abstract: A hollow fiber fluid separation device includes a hollow fiber cartridge, comprising a plurality of hollow fiber membranes arranged around a central tubular core, a first tubesheet and a second tubesheet encapsulating respective distal ends of the hollow fiber bundle. The tubesheets have boreholes in fluid communication with bores of the hollow fiber membrane. In at least one of the tubesheets, the boreholes are formed radially and are in communication with the central tubular core. The hollow fiber fluid separation device can be utilized in liquid separation applications such as ultrafiltration and in gas separation processes such as air separation. The design disclosed herein is light weight and compact and is particularly advantageous at high operating temperatures when the pressure of the feed fluid introduced into the bores of hollow fibers is higher than the pressure on the shell side of the device.

Abstract: There is disclosed an asymmetric gas separation membrane exhibiting both improved gas separation performance and improved mechanical properties, which is made of a soluble aromatic polyimide comprised of a repeating unit represented by general formula (1): wherein B in general formula (1) B comprises 10 to 70 mol % of tetravalent unit B1 represented by general formula (B1) and 90 to 30 mol % of tetravalent unit B2 represented by general formula (B2), and A in general formula (1) comprises 10 to 50 mol % of bivalent unit A1 represented by general formula (A1a) or the like and 90 to 30 mol % of bivalent unit A2 represented by general formula (A2a) or the like.

Abstract: An air dehydration membrane module is provided with a sweep gas which is taken from the waste gas of a pressure swing adsorption (PSA) unit. No additional compressor is required, other than the compressor forming part of the PSA unit. In another embodiment, the sweep gas includes the combination of dried product gas, taken from the dehydration membrane module, and a supplemental gas, which may be ambient air, or permeate gas from an air separation membrane, or waste gas from a PSA unit. An air ejector combines the streams, without the use of an additional compression step, and the combined gas is used as a sweep stream for the dehydration module. The invention also includes the method of selecting an optimum point at which the sweep gas is injected into the module.