Abstract: Methods and systems are provided for converting methane in a feed stream to acetylene. The method includes the further conversion of the acetylene to a hydrocarbon stream having olefins. The hydrocarbon stream is introduced into a supersonic reactor and pyrolyzed to convert at least a portion of the methane to acetylene. The reactor effluent stream is be treated to convert acetylene to another hydrocarbon, and in particular olefins. The method according to certain aspects includes controlling the level of contaminants in the hydrocarbon stream.

Abstract: Methods and systems are provided for converting methane in a feed stream to acetylene. The hydrocarbon stream is introduced into a supersonic reactor and pyrolyzed to convert at least a portion of the methane to acetylene. The reactor effluent stream may be treated to convert acetylene to nitrogen based hydrocarbon compounds such as pyridines. The method includes the reaction of acetylene with ammonia and controlling the ratio of acetylene to ammonia to generate the desired nitrogen based hydrocarbon compound.

Abstract: Methods and systems are provided for converting methane in a feed stream to acetylene. The method includes heat management in the process for further converting the acetylene stream to form a subsequent hydrocarbon stream. The hydrocarbon stream is introduced into a supersonic reactor and pyrolyzed to convert at least a portion of the methane to acetylene. The reactor effluent stream can be used to transfer heat to process streams used in downstream process units, and in particular streams that are fed to endothermic reactors.

Abstract: Methods and systems are provided for converting methane in a feed stream to acetylene. The method includes removing at least a portion of hydrides of arsenic, phosphorus, antimony, silicon, and boron from a hydrocarbon stream. The hydrocarbon stream is introduced into a supersonic reactor and pyrolyzed to convert at least a portion of the methane to acetylene. The reactor effluent stream may be treated to convert acetylene to another hydrocarbon process. The method according to certain aspects includes controlling the level of hydrides of arsenic, phosphorus, antimony, silicon, and boron in the hydrocarbon stream.

Abstract: Methods and systems are provided for converting methane in a feed stream to acetylene. The method includes processing the acetylene to form a stream having acrylic acid. The hydrocarbon stream is introduced into a supersonic reactor and pyrolyzed to convert at least a portion of the methane to acetylene. The reactor effluent stream is be treated to convert acetylene to acrylic acid. The method according to certain aspects includes controlling the level of carbon monoxide to prevent undesired reactions in downstream processing units.

Abstract: Methods and systems are provided for converting methane in a feed stream to acetylene. The hydrocarbon stream is introduced into a supersonic reactor and pyrolyzed to convert at least a portion of the methane to acetylene. The reactor effluent stream may be treated to convert acetylene to a process stream having aromatic compounds. The acetylene stream can be reacted to generate larger hydrocarbon compounds, which are passed to a cyclization and aromatization reactor to generate aromatics. The method according to certain aspects includes controlling the level of carbon oxides in the hydrocarbon stream.

Abstract: Methods and systems are provided for converting methane in a feed stream to acetylene. The hydrocarbon stream is introduced into a supersonic reactor and pyrolyzed to convert at least a portion of the methane to acetylene. The reactor effluent stream is further processed to generate larger hydrocarbons in a second reactor. The reactor effluent stream can be processed before the second reactor to remove waste products such as carbon monoxide and nitrogen in the reactor effluent stream.

Abstract: Methods and systems are provided for converting methane in a feed stream to acetylene. The method includes processing the acetylene to form a stream having vinyl acetate. A hydrocarbon stream is introduced into a supersonic reactor and pyrolyzed to convert at least a portion of the methane to acetylene. The reactor effluent stream is treated to convert acetylene to vinyl acetate. The method according to certain aspects includes controlling the level of carbon monoxide to prevent undesired reactions in downstream processing units.

Abstract: The present invention discloses a new type of high performance polymer membranes derived from aromatic polyimide membranes and methods for making and using these membranes. The polymer membranes described in the present invention were derived from aromatic polyimide membranes by crosslinking followed by thermal treating. The aromatic polyimide membranes were made from aromatic polyimide polymers comprising both pendent hydroxy functional groups ortho to the heterocyclic imide nitrogen and cross-linkable functional groups in the polymer backbone. The high performance polymer membranes showed significantly improved permeability for gas separations compared to the aromatic polyimide membranes without any treatment. The high performance polymer membranes also showed significantly improved selectivity for gas separations compared to the thermal-treated but non-UV-crosslinked aromatic polyimide membranes.

Abstract: The present invention provides a process for treating a natural gas stream comprising sending a natural gas stream to at least one membrane unit to produce a permeate stream containing a higher concentration of carbon dioxide and a retentate stream containing a lower concentration of carbon dioxide. Then the retentate stream is sent to an adsorbent bed to remove carbon dioxide and other impurities to produce a natural gas product stream. The regeneration gas stream is sent through the molecular sieve adsorbent bed to desorb the carbon dioxide. In one process flow scheme, the regeneration stream is combined with the permeate stream from the membrane unit. Then the combined stream is sent to an absorbent column to remove carbon dioxide from the permeate stream to produce a second natural gas product stream. In the alternative flow scheme, a second membrane unit is used to improve efficiency.

Abstract: The present invention involves the use of a multi-stage membrane system for gas, vapor, and liquid separations. In this multi-stage membrane system, high selectivity and high permeance or at least high selectivity polybenzoxazole membranes or cross-linked polybenzoxazole membranes are applied for a pre-membrane or both the pre-membrane and the secondary membrane. A primary membrane can be from conventional glassy polymers. This multi-stage membrane system can reduce inter-stage compression cost, increase product recovery and product purity for gas, vapor, and liquid separations. It can also save the cost compared to the system using all the high cost polybenzoxazole membranes or cross-linked polybenzoxazole membranes.

Abstract: The present invention discloses a new type of high performance polymer membranes prepared from aromatic polyimide membranes by thermal treating and crosslinking and methods for making and using these membranes. The polymer membranes were prepared from aromatic polyimide membranes by thermal treating under inert atmosphere followed by crosslinking preferably by using a UV radiation source. The aromatic polyimide membranes were made from aromatic polyimide polymers comprising both pendent hydroxy functional groups ortho to the heterocyclic imide nitrogen and cross-linkable functional groups in the polymer backbone. The membranes showed significantly improved selectivity and permeability for gas separations compared to the aromatic polyimide membranes without any treatment. The membranes can be fabricated into any convenient geometry and are not only suitable for a variety of liquid, gas, and vapor separations, but also can be used for other applications such as for catalysis and fuel cell applications.

Abstract: The present invention discloses a new type of high performance polymer membranes prepared from aromatic polyimide membranes by thermal treating and crosslinking and methods for making and using these membranes. The polymer membranes were prepared from aromatic polyimide membranes by thermal treating under inert atmosphere followed by crosslinking preferably by using a UV radiation source. The aromatic polyimide membranes were made from aromatic polyimide polymers comprising both pendent hydroxy functional groups ortho to the heterocyclic imide nitrogen and cross-linkable functional groups in the polymer backbone. The membranes showed significantly improved selectivity and permeability for gas separations compared to the aromatic polyimide membranes without any treatment. The membranes can be fabricated into any convenient geometry and are not only suitable for a variety of liquid, gas, and vapor separations, but also can be used for other applications such as for catalysis and fuel cell applications.

Abstract: The present invention involves the use of a multi-stage membrane system for gas, vapor, and liquid separations. In this multi-stage membrane system, high selectivity and high permeance or at least high selectivity polybenzoxazole membranes or cross-linked polybenzoxazole membranes are applied for a pre-membrane or both the pre-membrane and the secondary membrane. A primary membrane can be from conventional glassy polymers. This multi-stage membrane system can reduce inter-stage compression cost, increase product recovery and product purity for gas, vapor, and liquid separations. It can also save the cost compared to the system using all the high cost polybenzoxazole membranes or cross-linked polybenzoxazole membranes.

Abstract: The present invention involves the use of a multi-stage membrane system for gas, vapor, and liquid separations. In this multi-stage membrane system, high selectivity and high permeance or at least high selectivity polybenzoxazole membranes or cross-linked polybenzoxazole membranes are applied for a pre-membrane or both the pre-membrane and the secondary membrane. A primary membrane can be from conventional glassy polymers. This multi-stage membrane system can reduce inter-stage compression cost, increase product recovery and product purity for gas, vapor, and liquid separations. It can also save the cost compared to the system using all the high cost polybenzoxazole membranes or cross-linked polybenzoxazole membranes.

Abstract: The present invention discloses a new type of high performance polymer membranes prepared from aromatic polyimide membranes by thermal treating and crosslinking and methods for making and using these membranes. The polymer membranes were prepared from aromatic polyimide membranes by thermal treating under inert atmosphere followed by crosslinking preferably by using a UV radiation source. The aromatic polyimide membranes were made from aromatic polyimide polymers comprising both pendent hydroxy functional groups ortho to the heterocyclic imide nitrogen and cross-linkable functional groups in the polymer backbone. The membranes showed significantly improved selectivity and permeability for gas separations compared to the aromatic polyimide membranes without any treatment. The membranes can be fabricated into any convenient geometry and are not only suitable for a variety of liquid, gas, and vapor separations, but also can be used for other applications such as for catalysis and fuel cell applications.

Abstract: The present invention provides a process for treating a natural gas stream comprising sending a natural gas stream to at least one membrane unit to produce a permeate stream containing a higher concentration of carbon dioxide and a retentate stream containing a lower concentration of carbon dioxide. Then the retentate stream is sent to an adsorbent bed to remove carbon dioxide and other impurities to produce a natural gas product stream. The regeneration gas stream is sent through the molecular sieve adsorbent bed to desorb the carbon dioxide. In one process flow scheme, the regeneration stream is combined with the permeate stream from the membrane unit. Then the combined stream is sent to an absorbent column to remove carbon dioxide from the permeate stream to produce a second natural gas product stream. In the alternative flow scheme, a second membrane unit is used to improve efficiency.

Abstract: The present invention discloses a new type of high performance polymer membranes prepared from aromatic polyimide membranes by thermal treating and crosslinking and methods for making and using these membranes. The polymer membranes were prepared from aromatic polyimide membranes by thermal treating under inert atmosphere followed by crosslinking preferably by using a UV radiation source. The aromatic polyimide membranes were made from aromatic polyimide polymers comprising both pendent hydroxy functional groups ortho to the heterocyclic imide nitrogen and cross-linkable functional groups in the polymer backbone. The membranes showed significantly improved selectivity and permeability for gas separations compared to the aromatic polyimide membranes without any treatment. The membranes can be fabricated into any convenient geometry and are not only suitable for a variety of liquid, gas, and vapor separations, but also can be used for other applications such as for catalysis and fuel cell applications.

Abstract: The present invention involves the use of a multi-stage membrane system for gas, vapor, and liquid separations. In this multi-stage membrane system, high selectivity and high permeance or at least high selectivity polybenzoxazole membranes or cross-linked polybenzoxazole membranes are applied for a pre-membrane or both the pre-membrane and the secondary membrane. A primary membrane can be from conventional glassy polymers. This multi-stage membrane system can reduce inter-stage compression cost, increase product recovery and product purity for gas, vapor, and liquid separations. It can also save the cost compared to the system using all the high cost polybenzoxazole membranes or cross-linked polybenzoxazole membranes.

Abstract: The present invention discloses a new type of high performance polymer membranes derived from aromatic polyimide membranes and methods for making and using these membranes. The polymer membranes described in the present invention were derived from aromatic polyimide membranes by crosslinking followed by thermal treating. The aromatic polyimide membranes were made from aromatic polyimide polymers comprising both pendent hydroxy functional groups ortho to the heterocyclic imide nitrogen and cross-linkable functional groups in the polymer backbone. The high performance polymer membranes showed significantly improved permeability for gas separations compared to the aromatic polyimide membranes without any treatment. The high performance polymer membranes also showed significantly improved selectivity for gas separations compared to the thermal-treated but non-UV-crosslinked aromatic polyimide membranes.