Abstract: A method for separating a raw feed gas stream using a plurality of membrane module stages. The raw feed gas stream may be from a biogas process. Off-gas from another unit process in the system, such as a temperature swing adsorption unit or liquefaction unit, may be used as a low pressure sweep gas on the low pressure side of at least one of the membrane module stages. In one example, the sweep gas is used in a first membrane module stage. In another example, a stripping membrane module stage is provided and the sweep gas is used in the stripping membrane module stage. Optionally, portions of the off-gas could be directed to other streams in the system for the purpose of balancing compressor power requirements.

Abstract: A process for sweetening a syngas stream, the process comprising the steps of: providing a syngas stream to a nonselective amine absorption unit, the sour syngas stream comprising syngas, carbon dioxide, and hydrogen sulfide; separating the syngas stream in the nonselective amine absorption unit to obtain an overhead syngas stream and an acid gas stream; introducing the acid gas stream to a membrane separation unit, the acid gas stream comprising hydrogen sulfide and carbon dioxide; separating the acid gas stream in the membrane separation unit to produce a retentate stream and a permeate stream, wherein the retentate stream comprises hydrogen sulfide, wherein the permeate stream comprises carbon dioxide; introducing the retentate stream to a sulfur recovery unit; processing the retentate stream in the sulfur recovery unit to produce a sulfur stream and a tail gas stream, wherein the sulfur stream comprises liquid sulfur.

Abstract: A centrifugal impeller having an axis of rotation extending from front to rear, and including a body extending around the axis of rotation, the body having a front portion and a rear portion of larger section than the front portion, the impeller also have blades projecting from a front face of the body, the body presenting a setback in its front face between two consecutive blades, which setback is situated at a circumferential distance from the two blades.

Abstract: The invention relates to a connecting piece (6) for fluid lines of an exhaust gas aftertreatment system (1), comprising a hollow body (6a) having at least three fluid connection points (14, 15), which are fluidically connected to each other in the hollow body (6a), at least two of the fluid connection points (15) being separated from a third fluid connection point (14) by means of respective membranes (19), each membrane (19) being permeable to a liquid and, when wetted by the liquid, being impermeable to a gas.

Abstract: There are provided a process for producing a zeolite membrane which, even when large, has few defects and which has higher separation performance than conventional zeolite membranes, and a zeolite membrane obtained by the process. In the process, the structure-directing agent is removed in the atmosphere having an O2 concentration of 22.0 vol % or more. Specifically, the process includes: a particle adhesion step of allowing zeolite particles functioning as seeds to flow down the surface of the substrate by means of the weight of the slurry itself, thereby adhering to the substrate and a membrane-forming step of forming a zeolite membrane on the substrate by immersing the substrate having the zeolite particles adhering thereto in sol containing the structure-directing agent for hydrothermal synthesis, thereby forming a zeolite membrane on the substrate.

Abstract: A process according to the invention is a process to separate an initial fluid stream comprising phosgene and hydrogen chloride in at least a first and a second fluid stream, said first fluid stream being a hydrogen chloride enriched and phosgene depleted gaseous stream, said second fluid stream being a hydrogen chloride depleted and phosgene enriched stream.

Abstract: An apparatus and a method for recovery of sulfur hexafluoride is provided. Sulfur hexafluoride (SF6) may be separated with high-concentration and improved recovery ratio through a multi-stage separation and recovery processes using a plurality of separation membrane modules, and as well, SF6 gas may be concentrated to maximize the SF6 recovery ratio before the separation and recovery processes through the separation membrane modules. Furthermore, sulfur dioxide (SO2) and moisture included in the SF6 waste gas may be removed effectively so as to extend the service life of the separation membrane modules.

Abstract: A method of manufacturing a filled polymeric membrane includes a first step of preparing a filler suspension having a solvent for a glassy polymer and nanometer-sized particles. The nanometer-sized particles in the filler suspension are aggregated in aggregates having an average aggregate size in the range between 50 nm and smaller than 200 nm. In a following step, the glassy polymer is added to the filler suspension to obtain a polymer suspension. Next, the glassy polymer is dissolved in the polymer suspension. In a next step, the polymer suspension is cast on a substrate, followed by a step of removing the solvent. A filled polymeric membrane includes aggregates of nanometer-sized filler particles. The membrane is used in pervaporation and nanofiltration.

Abstract: A process for recovering a gaseous component comprising at least one fluorine-containing compound from a mixture of gaseous compounds. The process includes, in a separation zone (12), bringing a mixture of gaseous constituents, including at least one fluorine-containing constituent, into contact with a gas permeable separating medium (16) comprising a polymeric compound, so that a first gaseous component comprising at least one fluorine-containing constituent is separated from a second gaseous component comprising the balance of the gaseous constituents. The first gaseous component is withdrawn from the separation zone as a permeate (34) or a retentate, while the second gaseous component is withdrawn from the separation zone as the retentate (26), when the first gaseous component is withdrawn as the permeate, and as the permeate, when the first gaseous component is withdrawn as the retentate.

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: A gas purification method of the present invention uses a carbon membrane having a molecular sieving action to purify at least one selected from the group consisting of a hydride gas, a hydrogen halide gas, and a halogen gas, each gas containing an impurity at 10 ppm or less. The present invention can be used for a recovery unit that recoveries a used gas to reuse it as an ultrapure semiconductor material gas, and a unit or equipment that produces or charges an ultrapure semiconductor material gas.

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: A catalytic process for preparing chlorine from hydrogen chloride, which includes recycle of process streams with reduced accumulation of inert gases in the system is provided. The process includes a step wherein a compressed liquid stream comprising chlorine, carbon dioxide and oxygen is recycled into a column countercurrent to the ascending gas phase and feeding part of the chlorine-rich liquid phase leaving the bottom of the column back into the top of the column. Carbon dioxide present in the ascending gas stream is dissolved out of the gas stream and can later be separated from chlorine without problems by distillation.

Abstract: A process for recovering a gaseous component comprising at least one fluorine-containing compound from a mixture of gaseous compounds. The process includes, in a separation zone (12), bringing a mixture of gaseous constituents, including at least one fluorine-containing constituent, into contact with a gas permeable separating medium (16) comprising a polymeric compound, so that a first gaseous component comprising at least one fluorine-containing constituent is separated from a second gaseous component comprising the balance of the gaseous constituents. The first gaseous component is withdrawn from the separation zone as a permeate (34) or a retentate, while the second gaseous component is withdrawn from the separation zone as the retentate (26), when the first gaseous component is withdrawn as the permeate, and as the permeate, when the first gaseous component is withdrawn as the retentate.

Abstract: A gas purification method of the present invention uses a carbon membrane having a molecular sieving action to purify at least one selected from the group consisting of a hydride gas, a hydrogen halide gas, and a halogen gas, each gas containing an impurity at 10 ppm or less. The present invention can be used for a recovery unit that recoveries a used gas to reuse it as an ultrapure semiconductor material gas, and a unit or equipment that produces or charges an ultrapure semiconductor material gas.

Abstract: Membrane, methods of making membranes, and methods of separating gases using membranes are provided. The membranes can include at least one hydrophilic polymer, at least one cross-linking agent, at least one base, and at least one amino compound. The methods of separating gases using membranes can include contacting a gas stream containing at least one of CO2, H2S, and HCl with one side of a nonporous and at least one of CO2, H2S, and HCl selectively permeable membrane such that at least one of CO2, H2S, and HCl is selectively transported through the membrane.

Abstract: Provided is a novel system and apparatus for producing primary standard gas mixtures. The system includes providing a gas permeation device having a constant diffusion rate into a temperature controlled enclosure; connecting a supply source of a component to the permeation device; routing the component from the gas permeation device to a product container until a desired amount of said component in the product container is reached; and supplying a balance of purified gas to the product container to obtain a known concentration of component in the primary standard gas mixture.

Abstract: A method for separating aromatic hydrocarbons from a feed stream. The method includes flowing the feed stream through a first channel within a first wafer assembly that may contain an underflow distribution weir. Next, the feed stream is exposed to a first thin film polymer membrane. A stream permeates through the first thin film polymer membrane, and the permeate is produced from the first wafer assembly. The retentate is directed via a redistribution tube to a second wafer assembly that may contain an underflow distribution weir. This retentate is exposed to a second thin film polymer membrane. A second permeate stream is created that permeates through the second thin film polymer membrane. The second permeate stream is flown into the permeate zone and ultimately produced from the second wafer assembly. An apparatus for separating aromatic components from a feed stream is also disclosed. In the preferred embodiment, the apparatus includes a series of tandem wafer assemblies.

Abstract: A method for separating aromatic hydrocarbons from a feed stream. The method includes flowing the feed stream through a first channel within a first wafer assembly that may contain an underflow distribution weir. Next, the feed stream is exposed to a first thin film polymer membrane. A stream permeates through the first thin film polymer membrane, and the permeate is produced from the first wafer assembly. The retentate is directed via a redistribution channel (such as a tube) to a second wafer assembly that may contain an underflow distribution weir. This retentate is exposed to a second thin film polymer membrane. A second permeate stream is created that permeates through the second thin film polymer membrane. The second permeate stream is conducted into the permeate zone and ultimately produced from the second wafer assembly. An apparatus for separating aromatic components from a feed stream is also disclosed. In the preferred embodiment, the apparatus includes a series of tandem wafer assemblies.

Abstract: The present invention relates to a novel process for the preparation of high-purity chemicals with an extremely low particle count, such as ammonia gas, hydrogen fluoride and hydrogen chloride, which are also used as aqueous solutions in semiconductor technology the corrosive gas is enriched with an absorbent which is miscible with the gas and in which impurities present in the gas are soluble, and the gas is subsequently subjected to membrane filtration.

Abstract: Gas-impermeable membranes containing a molten salt electrolyte in an electron-conducting matrix provide for mixed ion and electron conduction across the membrane. The membranes mediate transport of a selected ion for gas separation and or catalytic reactions at the membrane surface. The membranes are useful in catalytic membrane reactors, particularly for gas separation and full or partial oxidation reactions. The membranes are of particular interest for mediation of oxide ions, such as carbonate, for carbon dioxide separation or for partial oxidation reactions. Catalytic membrane reactors can incorporate catalyst layers on the membrane surfaces and or three-dimension catalysts, e.g., packed-bed catalysts, in the oxidation zone or the reduction zone of the reactor. The invention also relates to methods of gas separation and method for generating products employing the membranes and catalytic membrane reactors of this invention.

Abstract: A method for the recovery or separation of sulfur oxyfluorides from gas mixtures, in which the gas mixture passes through at least one adsorption stage or membrane stage containing or consisting of zeolites with a modulus >10. The sulfur oxyfluorides fixed to the adsorbent may be made available for use after desorption. The sulfur oxyfluorides enriched through the membrane can be re-used directly.

Abstract: The invention relates to a method and apparatus for separating toxic compounds from gaseous mixtures, and more particularly to a method and a portable apparatus for the continuous removal of fluorine and compounds thereof from gaseous mixtures.

Abstract: A halide gas separating and collecting device for separating and collecting halide gas from mixed gas containing the halide gas, wherein at least first and second stage separating membrane modules are stacked in multiple stages. The method comprises: feeding the mixed gas to the inlet of the first stage separating membrane module, feeding the gas passed through the previous separating membrane module to the inlets of the second and subsequent stage separating membrane modules, recycling the gas unpassed through the second and subsequent stage separating membrane modules to the inlet of the first stage separating membrane module, and controlling the flow of gas unpassed through the first stage separating membrane module by a control valve connected to the unpassed gas outlet of the first stage separating membrane module, whereby the halide gas can be separated and collected as unpassed gas at a high density and a high collection rate.

Abstract: A process and a plant for removing the gaseous fluorocompounds or fluorosulphur compounds, such as CF4, C2F6, and SF6, present in a stream of xenon and/or krypton, by permeation via one or more membranes, such as polymer membranes. The xenon and/or krypton thus produced may then be further purified or separated by cryogenic distillation. Prior to the permeation step, the other impurities, particularly the hydrocarbons, may be removed by oxidative catalysis and subsequent adsorption of the carbon dioxides and of the water produced. The xenon, the krypton and the xenon/krypton mixtures free of gaseous fluorocompounds or fluorosulphur compounds and purified by such process can be used as plasma propulsion gas, especially for satellites, or as inter-pane insulation gas for a sealed unit, particularly for double-glazing windows.

Abstract: A method for the recovery or separation of sulfur oxyfluorides from gas mixtures, in which the gas mixture passes through at least one adsorption stage or membrane stage containing or consisting of zeolites with a modulus >10. The sulfur oxyfluorides fixed to the adsorbent may be made available for use after desorption. The sulfur oxyfluorides enriched through the membrane can be re-used directly.

Abstract: The process is characterised by sulfonating a partially brominated poly(phenylene oxide). The gas separation material so formed may be made into a membrane and is useful in separating component gases from a gas mixture.

Abstract: The separation factor with respect to a gas binary of a selectively gas permeable membrane of a fluoropolymer can be increased by fabricating the membrane from a composition of a blend of the fluoropolymer with a nonfugitive, nonpolymeric fluorinated adjuvant. The composition can be made by dissolving the adjuvant and the polymer in a suitably compatible solvent then forming the membrane from the solution for example by casting, dipping, or spraying the solution on a substrate and devolatilizing the solvent. The extent of the selectivity increase varies widely with the combination of fluoropolymer and adjuvant and largely increases in direct relation with the proportion of adjuvant in the membrane composition.

Abstract: A process for separating at least one of CF4 and C2F6 from a gas. The process includes the steps of: (a) contacting a gas mixture comprising (i) at least one of CF4 and C2F6, (ii) at least one of NF3, CHF3, and N2, and (iii) SF6 with a membrane at conditions effective to obtain a retentate stream rich in SF6 and at least one of CF4 and C2F6, and a permeate stream rich in at least one of NF3, CHF3, and N2; and (b) contacting the retentate stream with an adsorbent at conditions effective to adsorb SF6 and produce a product stream rich in at least one of CF4 and C2F6.

Abstract: A method for the separation and recovery of fluorochemicals from a gas stream containing a diluent gas and fluorochemicals by first contacting the gas stream with a membrane system in one or more stages where the membrane(s) is selectively more permeable to the diluent gas than the fluorochemicals to result in a permeate stream rich in diluent gas and retentate rich in fluorochemicals, thereafter subjecting retentate the gas stream to a purification by distillation or adsorption resulting in a product stream enriched in fluorochemicals and a purified diluent stream. The purified diluent stream is used as a purge stream and/or a recycle stream together with the permeate stream to a vacuum pump upstream of the membrane separation step.

Abstract: A process for separating chlorine from other low-boiling components of a gas-phase mixture. The invention involves three separation steps: condensation, flash evaporation and membrane separation. The steps are integrated together in such a way as to provide a good separation between the components, and to avoid creation of secondary streams that need additional treatment. The invention is particularly useful for treatment of gas streams from chlor-alkali processes.

Abstract: An improved process is disclosed for separating and recovering a fluorocarbon and hydrogen chloride (HCl) from a gaseous fluorocarbon/HCl mixture, wherein the fluorocarbon and HCl are difficult to separate by conventional means because of the presence or potential formation of an azeotrope or azeotrope-like composition in the mixture, such process comprising using a semi-permeable membrane unit to form a fluorocarbon-depleted stream and a fluorocarbon-enriched stream which may then be further processed individually by distillation.

Abstract: A process for separating the components of a gas mixture, including a sterilant gas and a diluent gas is disclosed. The gas mixture is fed to a membrane separation unit within which a perm-selective membrane is located which allows migration of diluent gas and sterilant gas at different rates. Both sterilant-rich and diluent-rich gas streams are withdrawn from the membrane separation unit and optionally recovered or further processed to a less hazardous compound. The process may be utilized to separate and treat the constituents of the exhaust gases from a chemical sterilization process of which the common components are olefin oxides such as ethylene oxide as a sterilant and chlorofluorocarbons (freon) such as dichlorodifluoromethane (CFC-1) as a diluent.

Abstract: A process for the removal of at least one non-water vapor component of a vaporous mixture, the basic process comprising directing a vaporous mixture against the feed side of a membrane, directing a condensable vapor sweep stream past the permeate side of the membrane in a manner such that the flow of the condensable vapor sweep is substantially countercurrent to the flow of the vaporous mixture, thereby transporting at least a portion of at least one non-water vapor component of the vaporous mixture from the feed side to the permeate side of the membrane to form a combined permeate side mixture of condensable vapor and at least one non-water vapor transported component.

Abstract: A membrane process for separating chlorine from chlorine-containing gas streams is disclosed. The process employs a permselective membrane that is selective to chlorine and is stable in the long-term presence of chlorine. The process can be used to treat tail-gas from chlor-alkali plants, for example.

Abstract: A process for removing inorganic components from water is disclosed. The process involves gas stripping followed by membrane separation treatment of the stripping gas. The stripping step can be carried out using one or multiple gas strippers and using air or any other gas as stripping gas. The membrane separation step can be carried out using a single-stage membrane unit or a multistage unit. Apparatus for carrying out the process is also disclosed. The process is particularly suited for treatment of contaminated groundwater or industrial wastewater.

Abstract: A process for treating a gas stream to remove or recover a condensable component. The process involves a condensation step followed by a membrane concentration step. The process is useful in treating raw gas streams containing low concentrations of the condensable component, in treating small-volume raw gas streams, as an alternative to processes that require multistage membrane separation systems, in treating raw gas streams that have the potential to form explosive mixtures, or in situations where the treated gas stream composition must meet narrow target specifications.

Abstract: A process for removing organic compounds from water is disclosed. The process involves gas stripping followed by membrane separation treatment of the stripping gas. The stripping step can be carried out using one or multiple gas strippers and using air or any other gas as stripping gas. The membrane separation step can be carried out using a single-stage membrane unit or a multistage unit. Apparatus for carrying out the process is also disclosed. The process is particularly suited for treatment of contaminated groundwater or industrial wastewater.

Abstract: A process for removing and recovering a condensable vapor from a gas stream by a membrane contactor is disclosed wherein a gas stream containing a condensable vapor is circulated on one side of hollow fiber membranes while cool extraction fluid is circulated on the other side under a total pressure differential, thereby condensing the condensable vapor in the gas stream, the condensed vapor permeating the membrane and becoming entrained in the cool extraction fluid.