Abstract: A process for the recovery of carbon dioxide from a gas mixture that includes pretreating a gas mixture comprising carbon dioxide, water vapor, and one or more light gases in a pretreating system to form a cooled gas mixture, fractionating the cooled gas mixture to recover a bottoms fraction comprising carbon dioxide and an overheads fraction comprising carbon dioxide and the light gases, passing the overheads fraction over a membrane selective to carbon dioxide to separate a carbon dioxide permeate from a residue gas comprising the light gases, recycling the carbon dioxide permeate to the pretreating system, and recovering at least a portion of the bottoms fraction as a purified carbon dioxide product stream is described.

Abstract: The present invention discloses a new process of treating natural gas using high gas permeability polybenzoxazole polymer membranes operated at high temperatures that can provide sufficient dew point margin for the product gas. The high gas permeability polybenzoxazole polymer membranes can be used for a single stage membrane system or for the first stage membrane in a two stage membrane system for natural gas upgrading. Simulation study has demonstrated that a costly membrane pretreatment system such as a MemGuard™ system will not be required in the present new process. The new process can achieve significant capital cost saving and reduce the existing membrane footprint greater than 50%.

Abstract: A membrane-based gas separation process for treating gas streams that contain methane in low concentrations. The invention involves flowing the stream to be treated across the feed side of a membrane and flowing a sweep gas stream, usually air, across the permeate side. Carbon dioxide permeates the membrane preferentially and is picked up in the sweep air stream on the permeate side; oxygen permeates in the other direction and is picked up in the methane-containing stream. The resulting residue stream is enriched in methane as well as oxygen and has an EMC value enabling it to be either flared or combusted by mixing with ordinary air.

Abstract: The present invention provides for a process for purifying carbon monoxide-containing gas streams that contain impurities such as hydrocarbons by using a cryogenic adsorption process. Preferably this process is a temperature swing adsorption process at cryogenic temperatures below ?75° C. Alternatively, the carbon monoxide-containing gas streams may be purified using the cryogenic adsorption process with membrane separation units or vacuum swing adsorption units or cryogenic distillation.

Abstract: Polymerizable ionic liquid monomers and their corresponding polymers (poly(ionic liquid)s) are created and found to exhibit high CO2 sorption. The poly(ionic liquid)s have enhanced and reproducible CO2 sorption capacities and sorption/desorption rates relative to room-temperature ionic liquids. Furthermore, these materials exhibit selectivity relative to other gases such as nitrogen, methane, and oxygen. They are useful as efficient separation agents, such sorbents and membranes. Novel radical and condensation polymerization approaches are used in the preparation of the poly(ionic liquids).

Abstract: A process for removing carbon dioxide or nitrogen from gas, especially natural gas. The process uses three membrane separation stages without compression between the second and third stages.

Abstract: A method of removing carbon monoxide from an oxygen carrier including setting a carbon monoxide bonded oxygen carrier solution across a separation membrane from an oxygen-dissolved solution; and exposing the setting part to the light and a method of removing carbon monoxide from an oxygen carrier including setting a carbon monoxide oxygen carrier solution across a hollow fiber separation membrane from an oxygen-dissolved solution; and exposing the setting part to light.

Abstract: The invention relates to a method for reducing the carbon dioxide concentration in air of a closed or partially closed unit of space. The inventive method may comprise the steps of removing an air flow from the unit of space, guiding the air flow in a membrane system that may contain at least one membrane module having a CO2/O2 selectivity of greater than 2, removing the carbon dioxide permeated through the membrane, and returning the air flow that has been depleted of carbon dioxide in the membrane system to the unit of space. The inventive method may be optionally combined with an oxygen enrichment method. The invention also relates to corresponding devices for carrying out the inventive method.

Abstract: A composition of and a method of making high performances crosslinked membranes are described. The membranes have a high resistance to plasticization by use of crosslinking. The preferred polymer material for the membrane is a polyimide polymer comprising covalently bonded ester crosslinks. The resultant membrane exhibits a high permeability of CO2 in combination with a high CO2/CH4 selectivity. Another embodiment provides a method of making the membrane from a monesterified polymer followed by final crosslinking after the membrane is formed.

Abstract: The invention relates to gas separation, in particular to separation of CO2 from CO2-rich liquids, particularly from CO2 absorption liquids used in the removal of CO2 from off-gases or product flows, such as natural gas or synthesis gas. According to the invention, CO2 is separated from a CO2-rich liquid by a method comprising a step wherein, under elevated pressure, said liquid is contacted with a membrane based on polyacetylene substituted with trimethylsilyl groups such that the pressure across the membrane is at least 1 bar and that at least a part of the CO2 is transported from the liquid through the membrane.

Abstract: Carbon dioxide or other gases can be separated from gas streams using ionic liquid, such as in an electrochemical cell. For example, a membrane can contain sufficient ionic liquid to reduce ionic current density of at least one of protons and hydroxyl ions, relative to carbon-containing ionic current density. A gas stream containing carbon dioxide can be introduced on a cathode side, while a source of hydrogen gas can be introduced on the anode side of the membrane. Operation of an electrochemical cell with such a membrane can separate the carbon dioxide from the gas stream and provide it at a separate outlet.

Abstract: The present disclosure provides a method and apparatus for extracting carbon dioxide (CO2) from a fluid stream and for delivering that extracted CO2 to controlled environments for utilization by a secondary process. Various extraction and delivery methods are disclosed specific to certain secondary uses, included the attraction of CO2-sensitive insects, the ripening and preservation of produce, and the neutralization of brine.

Abstract: The present invention relates to the selective separation of carbon dioxide (“CO2”) from nitrogen (“N2”) in streams containing both carbon dioxide and nitrogen utilizing a zeolitic imidazolate framework (“ZIF”) material. Preferably, the stream to be separated is fed to the present process in a substantially gaseous phase. In preferred embodiments, the current invention is utilized in a process to separate carbon dioxide from combustion gas (e.g., flue gas) streams preferably for sequestration of at least a portion of the carbon dioxide produced in combustion processes.

Abstract: The invention comprises a process of removing carbon dioxide from a natural gas feed stream comprising sending a natural gas feed stream comprising methane and carbon dioxide through an adsorbent bed to produce a carbon dioxide depleted methane rich product stream after removal of carbon dioxide. The adsorbent bed is regenerated and then the spent regeneration gas stream cooled to produce a cooled spent regeneration gas stream that is sent to a membrane element. A permeate stream passes through the membrane element and a residue stream passes by the membrane element without passing through said membrane element. Substantially all of the carbon dioxide and a minor portion of the methane comprises the permeate stream which is disposed of and a major portion of the methane and a minor portion of the carbon dioxide comprises the residue stream which is then recirculated to the regeneration gas stream.

Abstract: A nonporous metal carbonate membrane for selective separation of CO2 from a CO2-containing fluid having a porous substrate having a feed side and a permeate side. The membrane is also suitable for removal of H2S that may be present in the fluid.

Abstract: A polyimide MMC membrane useful for the production of oxygen-enriched air or nitrogen-enriched-air, for the separation of carbon dioxide from hydrocarbons or nitrogen, and the separation of helium or hydrogen from various streams. Membranes of polyimide polymers, such as polyimide polymers sold under the tradename P-84, are mixed with molecular sieve materials, such as SSZ-13, to make MMC membranes. The MMC membranes of the invention provide improved membrane performance compared to polymer only membranes, particularly when used to form asymmetric film membranes or hollow fiber membranes. The MMC films exhibit consistent permeation performance as dense film or asymmetric membranes, and do not interact with components of the process streams, such as organic solvents. The membranes of the invention exhibit particularly surprisingly good selectivity for the fluids of interest.

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: A process and equipment for treating natural gas produced by a well that has recently been stimulated, and that contains an undesirably high concentration of the fracturing gas used to stimulate the well. The process involves treating the gas by membrane separation, and provides for control of treatment parameters to compensate for the changing concentration of fracturing gas in the produced gas, as well as changes in gas flow rate.

Abstract: A carbon dioxide permeable membrane is described. In some embodiments, the membrane includes a body having a first side and an opposite second side; a plurality of first regions formed from a molten carbonate having a temperature of about 400 degrees Celsius to about 1200 degrees Celsius, the plurality of first regions forming a portion of the body and the plurality of first regions extending from the first side of the body to the second side of the body; a plurality of second regions formed from an oxygen conductive solid oxide, the plurality of second regions combining with the plurality of first regions to form the body and the plurality of second regions extending from the first side of the body to the second side of the body; and the body is configured to allow carbon dioxide to pass from the first side to the second side.

Abstract: The present invention provides a method for preparing silica containing molecular sieves which may be mixed with an organic polymer to create a mixed matrix membrane. Further, this invention includes a method of making such a mixed matrix membrane and the membrane itself. A process for separating component gases from a mixture using the subject mixed matrix membrane is also described. The method for preparing silica containing molecular sieves comprises super water washing silica containing molecular sieves to produce water washed molecular sieves which are substantially free of surface remnants. Super water washing also ideally lowers the concentration of alkali metals in the molecular sieves.

Abstract: The present invention includes a method, composition and apparatus for forming a nanoparticle filled polymer having similar gas selectivity and greater gas permeability than the native polymer. The nanoparticle filled polymer includes one or more polymeric materials and one or more nanoparticles dispersed within the one or more polymeric materials that increasing the permeability of the nanoparticle filled polymers relative to the permeability of the native polymer membrane.

Abstract: A gas-separation membrane module assembly and a gas-separation process using the assembly. The assembly includes a set of tubes, each containing gas-separation membranes, arranged within a housing. The housing contains a tube sheet that divides the space within the housing into two gas-tight spaces. A permeate collection system within the housing gathers permeate gas from the tubes for discharge from the housing.

Abstract: The present invention is for novel high performance cross-linkable and cross-linked mixed matrix membranes and the use of such membranes for separations such as for CO2/CH4, H2/CH4 and propylene/propane separations. More specifically, the invention involves the preparation of cross-linkable and cross-linked mixed matrix membranes (MMMs). The cross-linkable MMMs were prepared by incorporating microporous molecular sieves or soluble high surface area microporous polymers (PIMs) as dispersed microporous fillers into a continuous cross-linkable polymer matrix. The cross-linked MMMs were prepared by UV-cross-linking the cross-linkable MMMs containing cross-linkable polymer matrix such as BP-55 polyimide. Pure gas permeation test results demonstrated that both types of MMMs exhibited higher performance for CO2/CH4 and H2/CH4 separations than those of the corresponding cross-linkable and cross-linked pure polymer matrices.

Abstract: A feed gas is separated into a CO2-lean stream and a CO2-enriched stream at a CO2 enriching unit. The CO2-enriched gas is fed to a greenhouse to enhance plant growth. The feed gas may include air and/or vent gas from the greenhouse.

Abstract: Disclosed are a method and system for sweetening a raw natural gas feed stream using a multi-stage membrane separation process, and in embodiments a two-stage membrane separation process. The method and system also include use of a gas turbine which operates with an impure fuel gas stream (such as in the sense of having a relatively high CO2 and H2S acid gas contaminant content) as derived from a permeate gas stream obtained in at least the second stage of a membrane separation process, or later stages if more than two stages are employed. In embodiments, the gas turbine is coupled with an electrical generator, which generates electrical power that drives a compressor for the second stage (or higher) of the membrane separation process, as well as other process equipment associated therewith, such as air coolers and process pumps. Alternatively, the gas turbine can be coupled mechanically to the compressor employed.

Abstract: SAPO-34 membranes and methods for their preparation and use are described. The SAPO-34 membranes are prepared by contacting at least one surface of a porous membrane support with a synthesis gel comprising a first and a second templating agent. SAPO-34 crystals having a narrow size distribution were applied to the surface of the support prior to synthesis. A layer of SAPO-34 crystals is formed on at least one surface of the support. SAPO-34 membranes of the invention can have improved selectivity for certain gas mixtures, including mixtures of carbon dioxide and methane.

Abstract: This abstract discusses membranes needed to separate fluids for the production of oxygen-enriched air, nitrogen-enriched-air, for the separation of carbon dioxide from hydrocarbons, and the separation of hydrogen from various petrochemical and oil refining streams. Membranes are needed that provide a resistance to interaction with process components or contaminants, provide the mechanical strength required to withstand high membrane differential pressures and high process temperatures, and exhibit sufficient maximum strain such that membranes are not brittle and can easily be formed into desirable membrane forms. Membranes of polyimide polymers, particularly polyimide polymers sold under the trade name P-84, are annealed in a controlled annealing step to improve the mechanical properties of the polymers used to make separation membranes.

Abstract: Methods for separating carbon dioxide from a fluid stream at a temperature higher than about 200° C. with selectivity higher than Knudsen diffusion selectivity include contacting a porous membrane with the fluid stream to preferentially transport carbon dioxide. The porous membrane includes a porous support and a continuous porous separation layer disposed on a surface of the porous support and extending between the fluid stream and the porous support layer. The porous support comprises alumina, silica, zirconia, stabilized zirconia, stainless steel, titanium, nickel-based alloys, aluminum-based alloys, zirconium-based alloys or a combination thereof.

Abstract: There is disclosed a method of making a high performance carbon membranes from polymer membranes. The method comprising the steps of exposing polymer precursor compounds to a polar organic liquid before pyrolysis of the exposed polymer precursor compounds.

Abstract: A gas-separation membrane module assembly and a gas-separation process using the assembly. The assembly includes a set of tubes, each containing gas-separation membranes, arranged within a housing. The housing contains tube sheets that divide the space within the housing into three separate, gas-tight spaces, with the tubes mounted in the central space. Within this space, each tube has an aperture or hole in its wall that enables gas that has been retained on the feed side of the membranes to flow out of the tubes and into the space. The assembly can be used in various ways to carry out gas separation processes.

Abstract: A membrane and method for separating carbon dioxide from a mixture of gases, where the membrane includes expanded polytetrafluoroethylene and polysiloxane. The membrane is highly stable and can separate carbon dioxide at high flux in harsh environments and high temperatures, such as exhaust gases from power plants.

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: A porous membrane for separation of carbon dioxide from a fluid stream at a temperature higher than about 200° C. with selectivity higher than Knudsen diffusion selectivity. The porous membrane comprises a porous support layer comprising alumina, silica, zirconia or stabilized zirconia; a porous separation layer comprising alumina, silica, zirconia or stabilized zirconia, and a functional layer comprising a ceramic oxide contactable with the fluid stream to preferentially transport carbon dioxide. In particular, the functional layer may be MgO, CaO, SrO, BaO, La2O3, CeO2, ATiO3, AZrO3, AAl2O4, A1FeO3, A1MnO3, A1CoO3, A1NiO3, A2HfO3, A3CeO3, Li2ZrO3, Li2SiO3, Li2TiO3 or a mixture thereof; wherein A is Mg, Ca, Sr or Ba; A1 is La, Ca, Sr or Ba; A2 is Ca, Sr or Ba; and A3 is Sr or Ba.

Abstract: A fixed-site-membrane comprising a support structure coated with crosslinked polyvinylamine, wherein the crosslinking agent is a compound comprising a fluoride. The membrane comprises water, such as by being swelled in water vapour. A process for producing the membranes, and the use of such membranes for separation of carbon dioxide (CO2) from gas mixtures are disclosed.

Abstract: Membranes are used to separate fluids for the production of oxygen-enriched air, nitrogen-enriched-air, for the separation of carbon dioxide from hydrocarbons, and the separation of hydrogen from various petrochemical and oil refining streams. Membranes are discussed that provide a resistance to interaction with process components or contaminants, which can lead to plasticizing of the membrane, while providing the mechanical strength required to withstand high membrane differential pressures and high process temperatures. Membranes of blended polymers are used to improve the mechanical strength of the polymers used to make separation membranes. Specifically, polyimide polymers are combined with a blend polymer that is a polyamide and/or a polyamide-imde polymer. The resulting polymer mix is used to produce various forms of high strength, chemically resistant membranes, including hollow-fiber membranes that are suitable for high pressure, high temperature applications.

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: The invention relates to a method for reducing the carbon dioxide concentration in air of a closed or partially closed unit of space. The inventive method may comprise the steps of removing an air flow from the unit of space, guiding the air flow in a membrane system that may contain at least one membrane module having a CO2/O2 selectivity of greater than 2, removing the carbon dioxide permeated through the membrane, and returning the air flow that has been depleted of carbon dioxide in the membrane system to the unit of space. The inventive method may be optionally combined with an oxygen enrichment method. The invention also relates to corresponding devices for carrying out the inventive method.

Abstract: Disclosed are a conductive membrane able to selectively separate carbon dioxide from a gas mixture containing carbon dioxide, a manufacturing method thereof, and a method of separating carbon dioxide using the membrane. The conductive membrane for carbon dioxide separation includes molten carbonate, acting as a carbonate-ion conductor, and oxide, acting as an electronic conductor, and has infinite selectivity for carbon dioxide at high temperatures of 500° C. or more.

Abstract: The present invention provides for a process for producing carbon monoxide. A feed gas stream of hydrogen, carbon monoxide and carbon dioxide is directed to a membrane unit which separates the feed gas stream into two streams. The stream containing carbon monoxide is directed to second membrane unit for further purification and the steam containing the carbon dioxide and hydrogen is fed to a reverse shift reactor to produce more carbon monoxide. The carbon monoxide recovered from the reverse shift reactor is purified in a third membrane unit and directed back to the first membrane unit and is further purified and recovered as additional carbon monoxide product.

Abstract: A gas permeable membrane comprising a thin polymeric coating on a microporous backing, said gas permeable membrane being permeable permitting for oxygen and carbon dioxide at different flow rates, wherein the gas permeable membrane is made from a copolymer of a polyether and a polyamide enables the achievement of a controlled atmosphere in a cargo region, wherein the membrane is able to obtain and hold low concentrations of carbon dioxide and of oxygen in the atmosphere in the cargo region and to produce an “ideal” or optimum storage atmosphere which will ensure a retardation of respiratory activity within the container.

Abstract: A process is disclosed for shut-down of a membrane separation zone comprising a non-permeate side and a permeate side and processing a feed stream comprising a non-permeable component, a less-readily permeable, condensable component, and a readily permeable component. When the feed stream is not passed to the membrane separation zone, a purge stream is passed to the non-permeate side of the membrane separation to remove a residual gas stream and thereby prevent condensation of the less-readily permeable, condensable component upon depressurization and/or cooling of the membrane separation zone. This purge stream is provided by taking a feed stream, lowering its pressure which leads to cooling and then passing the cooled stream through a gas-liquid separator to removed condensed liquids.

Abstract: A carbon dioxide separation system comprises a first flow path for directing a fluid comprising carbon dioxide therethrough, a second flow path for directing a sweep fluid therethrough, and a separator comprising a material with selective permeability of carbon dioxide for separating the first and the second flow paths and for promoting carbon dioxide transport therebetween. A carbon dioxide separation unit is in fluid communication with the second flow path for separating the transported carbon dioxide from the sweep fluid.

Abstract: A carbon dioxide separation system comprises a heat exchanger having a first flow path for directing a fluid comprising carbon dioxide, for example an exhaust gas, therethrough and a second flow path for directing a heat transfer fluid therethrough, a separator comprising a material with selective permeability of carbon dioxide for separating the first and second flow paths and for promoting thermal transfer and carbon dioxide transport therebetween, and a condenser for condensing the heat transfer fluid to isolate the carbon dioxide.

Abstract: SAPO membranes and methods for their preparation and use are described. The SAPO membranes are prepared by contacting at least one surface of a porous membrane support with an aged synthesis gel. A layer of SAPO crystals is formed on at least one surface of the support. SAPO crystals may also form in the pores of the support. SAPO-34 membranes of the invention can have improved selectivity for certain gas mixtures, including mixtures of carbon dioxide and methane.

Abstract: A process for the removal of inert gases, such as nitrogen and carbon dioxide, from methane-containing gases, such as natural gas, including a first stage removal which lowers the total combined inert content to about less than 30% and a second stage removal utilizing a pressure swing adsorption process comprising one or more adsorbent beds comprising contracted titanosilicate-1 adsorbent, wherein the purified methane-containing gas contains less than about 6% total combined inerts.

Abstract: A method and apparatus for separating a component from a multi-component feed gas stream has a flow conduit (14) having a semi-permeable section (15) that permeates the component to be separated from feed gas stream (12). A sweep gas is provided at a first velocity on the permeate sides of flow conduit (14) and the velocity of sweep gas (13) is accelerated so that the velocity of sweep gas (13) along at least a portion of the permeate side of flow conduit (14) is greater than the first velocity. The mixture of permeate and sweep gas (13) is then decelerated by diffuser (20), thereby recovering as pressure a portion of the energy of feed gas stream (12).

Abstract: There is provided a high efficient gas separation membrane of two or more layers, which comprises a separating layer of 3-dimensional nanostructure and a supporting layer, wherein the 3-dimensional nanostructure can maximize a surface area per unit permeation area.

Abstract: A mixed matrix membrane for separating gas components from a mixture of gas components is disclosed. The membrane comprises a continuous phase polymer with inorganic porous particles, preferably molecular sieves, interspersed in the polymer. The polymer has a CO2/CH4 selectivity of at least 20 and the porous particles have a mesoporosity of at least 0.1 cc STP/g. The mixed matrix membrane exhibits an increase in permeability of least 30% with any decrease in selectivity being no more than 10% relative to a membrane made of the neat polymer. The porous particles may include, but are not limited to, molecular sieves such as CVX-7 and SSZ-13, and/or other molecular sieves having the required mesoporosity. A method for making the mixed matrix membrane is also described. Further, a method is disclosed for separating gas components from a mixture of gas components using the mixed matrix membrane with mesoporous particles.

Abstract: A process for removing carbon dioxide or nitrogen from gas, especially natural gas. The process uses three membrane separation stages without compression between the second and third stages.

Abstract: Gasses are separated using a molecular sieve having the CHA crystal structure and having a mole ratio of greater than 50 to 1500 of (1) an oxide selected from silicon oxide, germanium oxide or mixtures thereof to (2) an oxide selected from aluminum oxide, iron oxide, titanium oxide, gallium oxide or mixtures thereof.