Abstract: The disclosure relates generally to a gas separation membrane and a gas separation method in which at least one type of gas is separated and recovered from a gas mixture, using the gas separation membrane. The gas separation membrane is asymmetric and hollow and made of a polyimide material. The method of the invention provides a practical, high-performance technique for gas separation.

Abstract: A fluorinated ethylene-propylene polymeric membrane comprising a copolymer comprising 2,3,3,3-tetrafluoropropene and vinylidene fluoride is disclosed. The fluorinated ethylene-propylene polymeric membranes of the invention are especially useful in gas separation processes in air purification, petrochemical, refinery, and natural gas industries.

Abstract: An aircraft fuel tank flammability reduction method includes contacting a membrane filter with air feed, permeating oxygen and nitrogen from the air feed through the membrane, and producing filtered air from the filter. The filtered air is produced from the filter as a result of the membrane removing any hydrocarbons containing six or more carbon atoms to produce a total of 0.001 ppm w/w or less. An air separation method includes feeding air into a filter containing a hollow fiber membrane that exhibits the property of resisting degradation due to exposure to hydrocarbons containing six or more carbon atoms. The filter exhibits a pressure drop across the membrane of less than 5 psi. The method includes feeding the filtered air into an air separation module containing a hollow fiber membrane that exhibits a susceptibility to degradation from exposure to hydrocarbons containing six or more carbon atoms.

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: An equipment for carrying out a process for producing synthesis gas (S) from biomass, includes a storage unit (1) for biomass and means (3; 5, 6) to carry out pyrolysis and combustion of the biomass. The equipment further includes first or second heat exchanging means (7, 9; 15) to receive outgoing gases (CO2, N2 and H2O) from the means (3; 5, 6) to carry out pyrolysis and combustion of the biomass, a gas purification unit (10) to receive the outgoing gases (CO2, N2 and H2O) that are cooled in the first or second heat exchanging means (7, 9; 15), means (11) to supply a process gas (P) from the gas purification unit (10) to the first heat exchanging means (7, 9), and a reduction shaft (12) to carry out reduction of the process gas (P) discharged from the first heat exchanging means (7, 9).

Abstract: A filling pistol for the filling under pressure of an object essentially with nitrogen. The filling pistol has a housing with an inlet opening connectable to an air source, such as an air compressor, to supply air to the pistol. A separation device is incorporated downstream of and connected to the inlet opening to obtain essentially nitrogen-rich gas. An outlet opening is connected to the separation device and is connectable to the object to supply nitrogen-rich air from the filling pistol to the object. The separation device is provided between the air inlet and the nitrogen outlet of an exchangeable separation cartridge. An operating element sets the filling pistol to an operating condition to fill the object with nitrogen-rich air.

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 process for treating off-gas streams from reaction processes, and reaction processes including such gas separation. The invention involves flowing the off-gas across the feed side of a membrane, flowing a sweep gas stream, usually air, across the permeate side, and passing the permeate/sweep gas mixture to the reaction. The process recovers unreacted feedstock that would otherwise be lost in the waste gases in an energy-efficient manner.

Abstract: The present invention discloses blend polymer membranes comprising thermally rearranged polymers derived from aromatic polyimides containing ortho-positioned functional groups and methods for making and using these blend polymer membranes. The blend polymer membranes described in the current invention are prepared by heat treatment of blend polymer membranes comprising aromatic polyimides containing ortho-positioned functional groups such as —OH or —SH groups. In some instances, an additional crosslinking step is performed to improve the selectivity of the membrane. These blend polymer membranes have improved flexibility, reduced cost, improved processability, and enhanced selectivity and/or permeability compared to the comparable polymer membranes that comprise a single polymer.

Abstract: Disclosed is an exhaust gas treating system having an exhaust gas treating apparatus for carbon dioxide capture process which additionally removes harmful substances remaining in the gas discharged from the existing flue-gas desulfurization process by using separation membrane so as to efficiently carry out the carbon dioxide capture process. The exhaust gas treating system using polymer membrane, comprises a carbon dioxide capture equipment for capturing carbon dioxide from the exhaust gas of a boiler, a flue-gas denitrification equipment placed between the boiler and the carbon dioxide capture equipment, a dust-collecting equipment and a flue-gas desulfurization equipment.

Abstract: Embodiments of the invention provide venting and filtration systems with a membrane that is permeable to gas and substantially impermeable liquid. The systems can remove a gas from a liquid entrained with gas. The systems can include a reservoir in fluid communication with the membrane and a liquid outlet. The membrane can help prevent the gas from reaching the liquid outlet.

Abstract: Embodiments of the invention provide venting and filtration systems with a membrane that is permeable to gas and substantially impermeable liquid. The systems can remove a gas from a liquid entrained with gas. The systems can include a reservoir in fluid communication with the membrane and a liquid outlet. The membrane can help prevent the gas from reaching the liquid outlet.

Abstract: The present invention discloses microporous UZM-5 zeolite membranes, methods for making the same, and methods of separating gases, vapors, and liquids using the same. The small-pore microporous UZM-5 zeolite membrane is prepared by two different methods, including in-situ crystallization of one or more layers of UZM-5 zeolite crystals on a porous membrane support, and a seeding method by in-situ crystallization of a continuous second layer of UZM-5 zeolite crystals on a seed layer of UZM-5 zeolite crystals supported on a porous membrane support. The membranes in the form of disks, tubes, or hollow fibers have superior thermal and chemical stability, good erosion resistance, high CO2 plasticization resistance, and significantly improved selectivity over polymer membranes for gas, vapor, and liquid separations.

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: The invention relates to a hydrophobic, integrally asymmetrical hollow-fiber membrane made of a vinylidene fluoride homopolymer or copolymer, wherein the wall of the membrane has a microporous supporting layer having a sponge-like, open-pored, essentially isotropic pore structure without finger pores, the supporting layer extending across at least 90% of the wall thickness and having pores with an average diameter of less than 0.5 ?m. The hollow-fiber membrane is characterized in that it has a separating layer adjacent to the supporting layer on its outer surface and that it has an outer surface with a homogeneous, uniform structure without pores, a porosity in the range from 40 to 80 vol. %, a wall thickness from 25 to 100 ?m, a diameter of the lumen of the hollow-fiber membrane from 100 to 500 ?m, a permeability for nitrogen of at least 25 ml/(cm2·min·bar), and an elongation at break of at least 250%. The invention further relates to a method for producing hollow-fiber membranes of this type.

Abstract: A waste heat recovery system is provided. The waste heat recovery system includes a gas separation apparatus that includes a chamber and at least one membrane positioned within the chamber. The gas separation apparatus is configured to produce a retentate that includes at least a combustible gas and a permeate that includes at least a waste gas, wherein the waste gas includes at least a noncombustible gas. Moreover, the waste heat recovery system includes a burner that is coupled to the gas separation apparatus, wherein the burner is configured to receive the permeate and to combust the permeate such that heat is generated from the permeate. Further, a heat recovery steam generator is coupled to the burner and configured to recover heat generated by the burner.

Abstract: The invention relates to the use of carbon nanomaterials as a filtration material pervious to nitrogen dioxide and impervious to ozone. The invention also relates to the use of carbon nanomaterials having a specific surface, measured by the BET method, of 15 to 40 m2/g inclusive and a form factor, equal to the ratio (highest dimension/lowest dimension) of the nanomaterial, of 5 to 250 inclusive, as material for filtering a gas mixture containing nitrogen dioxide and ozone, being pervious to the nitrogen dioxide and impervious to the ozone. The invention can be used in the field of air pollution.

Abstract: Technologies are generally described for a membrane that may incorporate a graphene layer perforated by a plurality of nanoscale pores. The membrane may also include a gas sorbent that may be configured to contact a surface of the graphene layer. The gas sorbent may be configured to direct at least one gas adsorbed at the gas sorbent into the nanoscale pores. The nanoscale pores may have a diameter that selectively facilitates passage of a first gas compared to a second gas to separate the first gas from a fluid mixture of the two gases. The gas sorbent may increase the surface concentration of the first gas at the graphene layer. Such membranes may exhibit improved properties compared to conventional graphene and polymeric membranes for gas separations, e.g., greater selectivity, greater gas permeation rates, or the like.

Abstract: Technologies are generally described for perforated graphene monolayers and membranes containing perforated graphene monolayers. An example membrane may include a graphene monolayer having a plurality of discrete pores that may be chemically perforated into the graphene monolayer. The discrete pores may be of substantially uniform pore size. The pore size may be characterized by one or more carbon vacancy defects in the graphene monolayer. The graphene monolayer may have substantially uniform pore sizes throughout. In some examples, the membrane may include a permeable substrate that contacts the graphene monolayer and which may support the graphene monolayer. Such perforated graphene monolayers, and membranes comprising such perforated graphene monolayers may exhibit improved properties compared to conventional polymeric membranes for gas separations, e.g., greater selectivity, greater gas permeation rates, or the like.

Abstract: A vapor particle separator including a temperature controlled chamber for desorbing vapors from the particulates of an exhaust gas and a separation chamber including a micro porous membrane. The micro porous membrane provides an interface between at least one particle passageway and at least one vapor passageway through the separation chamber. The particle passageway extends from an entrance to the separation chamber to a particle exit from the separation chamber. The vapor passageway extends from the micro-porous membrane to a vapor exit from the separation chamber that is separate from the particle exit from the separation chamber.

Abstract: A method for filtration of harmful gas effluents from a nuclear power plant including the steps of providing a gas effluent from a nuclear power plant, the effluent including a mixture of gases; filtering the harmful, notably radioactive elements from the gas effluent by membrane separation through at least one membrane, the membrane separation being achieved by sifting, sorption and/or diffusion; storing the filtered harmful elements in storage reservoirs, and discharging the processed gas effluent to the atmosphere.

Abstract: The present invention is for high permeance and high selectivity blend polymeric membranes comprising poly(ethylene glycol) (PEG) and a highly permeable polymer selected from the group consisting of polymers of intrinsic microporosity (PIMs), tetrazole-functionalized polymers of intrinsic microporosity (TZPIMs), or mixtures thereof. The present invention also involves the use of such membranes for separations of liquids and gases.

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 nitrogen-permeable structure includes a porous support and a nitrogen-permeable membrane adjacent to the porous support. The nitrogen-permeable membrane includes a first metal and a second metal, wherein the first metal is selected from niobium, tantalum, and vanadium, and the second metal is different from the first metal.

Abstract: First, a first porous body is manufactured by stretching, in a uniaxial direction, a sheet made of polytetrafluoroethylene having a standard specific gravity of 2.155 or more, and a second porous body is manufactured by stretching, in biaxial directions, a sheet made of polytetrafluoroethylene. Next, the first porous body is integrated with the second porous body by stretching a laminate of the first porous body and the second porous body in the same direction as the uniaxial direction while heating the laminate at a temperature equal to or higher than a melting point of polytetrafluoroethylene. Thus, a porous polytetrafluoroethylene membrane is produced.

Abstract: A water-proof air-permeable filter (1) includes: a resin film (2) having formed therein a plurality of through pores (21); a treated layer (3) having hydrophobicity and oil repellency, and formed on at least one of both surfaces in the thickness direction of the resin film (2) such that the treated layer (3) has openings (31) at positions corresponding to the through pores (21); and a loop-shaped double-sided tape (4) stuck to an edge region of one of both surfaces in the thickness direction of the resin film (2), with the treated layer (3) interposed therebetween.

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: A permselective material has a polymer having an organosiloxane skeleton and containing a dispersed solid additive. When oxygen and nitrogen are passed through a membrane having the permselective material, the relation between the permeability coefficients [cm3·cm·sec?1·cm?2·cmHg?1] of oxygen and nitrogen at a temperature of 23±2° C. under a pressure difference of 1.05 atm to 1.20 atm through the membrane is expressed by Formula (1): 0.94 ? P ? ( O 2 ) P ? ( N 2 ) < 1 ( 1 ) where P(O2) denotes the permeability coefficient of oxygen, while P(N2) denotes the permeability coefficient of nitrogen.

Abstract: An asymmetric membrane contains a porous layer and a dense layer adjacent thereto. The porous layer and the dense layer are formed of a polymeric material. The porous layer and/or dense layer contains a filler. The amount of the filler is 11 parts by mass or more per 100 parts by mass of the polymeric material contained in the asymmetric membrane.

Abstract: A process for the production of a carbon hollow fiber membrane comprising: (i) dissolving at least one cellulose ester in a solvent to form a solution; (ii) dry/wet spinning the solution to form hollow fibers; (iii) deesterifying said hollow fibers with a base or an acid in the presence of an alcohol; (iv) if necessary, drying said fibers; (v) carbonizing the fibers; (vi) assembling the carbonized fibers to form a carbon hollow fiber membrane.

Abstract: One aspect of the present teachings includes a separation membrane arranged in a hollow case. A particular component concentration chamber and a particular component dilution chamber are arranged in series in the hollow case. The particular component concentration chamber is capable of increasing concentration of the particular component by allowing permeation of the particular gas through the separation membrane. The particular component dilution chamber is capable of increasing concentration of the particular component by not allowing permeation of the particular gas through the separation membrane. The particular component concentration chamber and the particular component dilution chamber are configured such that only a gas containing the particular component and permeated through the separation membrane or only a gas containing the particular component not permeated through the separation membrane in one of the chambers disposed on an upstream side (i.e.

Abstract: A system for providing nitrogen enriched air (NEA) from ambient air uses at least two gas separation membranes that are selectively gas permeable for oxygen and nitrogen. The oxygen/nitrogen selectivity and oxygen permeance of two of the membranes are different such that (1) the selectivity of first membrane is less than the second membrane and the oxygen permeance of first membrane is greater than the second membrane, or (2) the selectivity of first membrane is greater than the second membrane and the oxygen permeance of first membrane is less than the second membrane. The system is very compact, is energy efficient, and highly effective for generating NEA. It is ideally suited for mobile, remote and specialized end use applications, such as automotive vehicles, marine vessels, off-shore platform fuel storage and especially for supplying NEA to blanket ullage of onboard aircraft fuel storage tanks.

Abstract: There is provided a zeolite separation membrane-provided article having gaps or pores larger than pores inherent to zeolite crystals and controlled within an appropriate range and being capable of achieving both high permeability and high separability for components with small difference in adsorption properties or a component having a smaller molecular diameter than the diameter of the pores, a method for producing the same, a method for separating mixed fluids, and a device for separating mixed fluids. The zeolite separation membrane-provided article is provided with a zeolite membrane having an N2 gas permeation speed at room temperature of 1.0×10?6 mol·m?2·s?1·Pa?1 or more and a permeation speed ratio of 1,3,5-trimethylbenzene/N2 at room temperature of 0.17 or more and being free from dyeing caused by the impregnation with Rhodamine B.

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: A method of making a crosslinked polyimide membrane is described. A monoesterified membrane is formed from a monoesterified polyimide polymer. The monoesterified membrane is subjected to transesterification conditions to form a crosslinked membrane. The monoesterified membrane is incorporated with an organic titanate catalyst before or after formation of the monoesterified membrane. A crosslinked polyimide membrane made using the aforementioned method and a method of using the membrane to separate fluids in a fluid mixture, such as methane and carbon dioxide, are also disclosed.

Abstract: In an embodiment there is provided a fluid separation assembly. The assembly has a hollow fiber bundle with a plurality of hollow fiber membranes. The assembly further has a first tubesheet and a second tubesheet encapsulating respective ends of the hollow fiber bundle, wherein one of the tubesheets has a plurality of radial through openings formed in the tubesheet. The assembly further has a housing surrounding the hollow fiber bundle and the first and second tubesheets, the housing having a feed inlet port, a permeate outlet port, and a non-permeate outlet port. The feed gas, permeate gas, or non-permeate gas are introduced into or removed from the hollow fiber membranes via the plurality of radial through openings formed in the tubesheet, such that the radial through openings of the tubesheet intersect each or substantially each of the hollow fiber membranes.

Abstract: The present disclosure relates to a high molecular weight, monoesterified polyimide polymer. Such high molecular weight, monoesterified polyimide polymers are useful in forming crosslinked polymer membranes for the separation of fluid mixtures. According to its broadest aspect, the method of making a crosslinked membrane comprises the following steps: (a) preparing a polyimide polymer comprising carboxylic acid functional groups from a reaction solution comprising monomers and at least one solvent; (b) treating the polyimide polymer with a diol at esterification conditions in the presence of dehydrating conditions to form a monoesterified polyimide polymer; and (c) subjecting the monoesterified fiber to transesterification conditions to form a crosslinked fiber membrane, wherein the dehydrating conditions at least partially remove water produced during step (b). The crosslinked membranes can be used to separate at least one component from a feed stream including more than one component.

Abstract: There is provided a process for producing nitrogen-rich air by feeding a high temperature air at 150° C. or more to an air separation membrane module.

Abstract: A process for producing synthesis gas (S) from biomass, includes drying the biomass and gasifying the biomass. An equipment to carry out the process is also disclosed. The process further includes: subjecting the outgoing gases (CO2, N2 and H2O) from the gasifying step to a first heat exchange, where the outgoing gases (CO2, N2 and H2O) are cooled, purifying the outgoing gases (CO2, N2 and H2O) to achieve a process gas (P), the purification being effected by eliminating nitrogen (N2) from the outgoing gases (CO2, N2 and H2O), subjecting the process gas (P) to heat exchange, where the process gas (P) is heated, reducing the process gas (P) to synthesis gas (S), subjecting the synthesis gas (S) to heat exchange, where the synthesis gas (S) is cooled and supply air to the gasification is heated.

Abstract: Provided is a gas separation membrane having superior gas permeability, separation selectivity and mechanical properties. A gas separation membrane to separate at least one acid gas from a mix gas, comprising in this order: a first layer that is porous; a second layer that is a separation-active layer containing a compound having a molecular weight of 150,000 or less and capable oft interacting with the acid gas; and a third layer having high gas permeability.

Abstract: A shipboard system provides dry, oil-free utility air and inert gas for use on a marine vessel. A compressor converts ambient air into a pressurized air stream. The air stream is cooled by heat exchange with sea water in the vicinity of the vessel. The air stream is then dried in a dehydration membrane module, and some of the product of the dehydration module is taken for use as utility air. The remainder of the dried air is passed through an air separation module which includes a polymeric membrane. The product of the air separation module includes a nitrogen-enriched gas which is used as an inert gas on the vessel. The compressor is the only mechanically moving component of the system.

Abstract: A liquid degasser for a space device including a gas permeable material configured for contact with a flow of liquid to be de-gassed on one side and a vacuum on the other side, and wherein the gas permeable material allows gas in the liquid to diffuse to the vacuum to remove the gas from the liquid.

Abstract: The present invention is a biogas processing system having a compressor having a biogas input and output, a pump having a water input and output, a scrubber tower having a mixing chamber connected to a biogas input, a water pump input, a water output, and a processed biogas output, and a filtration member connected to the water output to remove contaminants from the water exiting the first scrubber tower. The system also includes devices for heating and cooling the recycled flow of water to enhance the ability of the water to absorb contaminants from the biogas and the ability of a stripper to remove absorbed contaminants from the water in a closed loop water system, and a controller for closely controlling the operating parameters of the system to achieve safe and optimal operation of the system.

Abstract: A method of continuously removing nitrogen from a blast furnace exhaust stream containing oxygen, nitrogen and unburned hydrocarbons in order to form a supplemental feed to a gas turbine engine containing residual hydrocarbon fuel by first removing entrained solid particulates in the blast furnace exhaust stream to create a substantially particulate-free gas, passing the particulate-free stream through at least one separator bed containing an adsorptive material capable of adsorbing nitrogen from air, adsorbing substantially all of the nitrogen as interstitial nitrogen on solids within the separator bed, feeding non-adsorbed hydrocarbon fuel and oxygen components leaving the separator to a gas turbine engine and removing the adsorbed nitrogen from the separator bed.

Abstract: To provide a simple highly-pure Xe retrieval method and device with high retrieval efficiency by functionally removing such elements as water, CO2 and FCs from waste gases from semiconductor production processes, such as the plasma etching, that contain low-concentration Xe. For samples containing xenon and fluorocarbon, this invention is characterized by having at least first adsorption means (A1) filled with synthetic zeolite with pore size of 4A or smaller and aluminum oxide, arranged serially, gas separation means (A2) composed of silicone or polyethylene hollow fiber gas separation membrane modules 4, second adsorption means (A3) filled with either activated carbon, synthetic zeolite with pore size of 5A or larger, molecular sieving carbon with pore size of 5A or larger, or a combination of these, and reaction means (A4) filled with calcium compounds as reactant.

Abstract: The present disclosure relates to a high molecular weight, monoesterified polyimide polymer. Such high molecular weight, monoesterified polyimide polymers are useful in forming crosslinked polymer membranes for the separation of fluid mixtures. According to its broadest aspect, the method of making a crosslinked membrane comprises the following steps: (a) preparing a polyimide polymer comprising carboxylic acid functional groups from a reaction solution comprising monomers and at least one solvent; (b) treating the polyimide polymer with a diol at esterification conditions in the presence of dehydrating conditions to form a monoesterified polyimide polymer; and (c) subjecting the monoesterified fiber to transesterification conditions to form a crosslinked fiber membrane, wherein the dehydrating conditions at least partially remove water produced during step (b). The crosslinked membranes can be used to separate at least one component from a feed stream including more than one component.

Abstract: A method and apparatus for reducing discharges into the atmosphere of mercury pollutants associated with dry process, precalciner cement manufacturing is shown. Raw feed meal used in cement production is heated in a special heating chamber to drive off volatile mercury pollutants, such as elemental mercury and mercury oxides. Preferably, the feed meal is heated to a temperature of at least 175° C. The gases that are driven off flow are then cooled to condense the mercury pollutants causing them to be adsorbed on carbon particles injected into the gas flow. The carbon particles containing the condensed mercury pollutants are then filtered out of gas flow, for example, using a fabric filter. The gas flow may be burned to destroy other volatile pollutants such as hydrocarbons and/or ammonia.

Abstract: A method (10) for the separation of gases involving the method steps of: i) passing an exhaust gas stream (27) containing CO2 through a first membrane separation system (30) to produce a pre-concentrated gas stream (34) containing at least carbon dioxide; and a reject stream; and ii) directing the pre-concentrated gas stream to at least one purification step (50) to produce a purified CO2 stream (55); wherein, sulphur-containing gases (SOx) are also substantially separated from the exhaust gas (27) by the first membrane separation step (30) into the pre-concentrated gas stream (34), and the purified CO2 stream (55) is substantially free of nitrogen gas.

Abstract: A method of separating components of a gas mixture, the method comprising: passing the gas mixture through a benzoxazole-based polymer membrane at a temperature of from about 30° C. to about 400° C., wherein the benzoxazole-based polymer membrane is represented by the formula: as is defined herein.

Abstract: A gas separation process for treating off-gas streams from reaction processes, and reaction processes including such gas separation. The invention involves flowing the off-gas across the feed side of a membrane, flowing a sweep gas stream, usually air, across the permeate side, and passing the permeate/sweep gas mixture to the reaction. The process recovers unreacted feedstock that would otherwise be lost in the waste gases in an energy efficient manner.