Abstract: Multilayer composite membranes are produced in a one-step coating process that provides an interior gas separation layer and an external defect sealing layer.

Abstract: Novel alkyl-substituted aromatic polyester gas separation membranes and the process of using such membranes to separate one or more gases from a gaseous mixture is disclosed. The polyesters are formed from aromatic alcohols of the formula ##STR1## where Z is independently alkyl groups having 1 to 10 carbon atoms, most preferably a tertiary butyl group, n is an integer from 0 to 4, preferably 1.

Abstract: The present invention relates to composite membranes and membranes which are formed from modified poly(phenylene oxide) polymers having improved film forming properties and separation characteristics. The present invention further relates to poly(phenylene oxide) polymer and modified poly(phenylene oxide) polymer, having improved membrane forming characteristics and processes for producing the same.

Abstract: A polyimide gas separation membrane containing repeating units derived from 9,9-disubstituted xanthene dianhydride is disclosed.

Abstract: In an apparatus for producing liquid nitrogen by supplying to a nitrogen gas separated from the atmosphere and then purified by an air separating device (4) into an insulated container (1) equipped with an extremely low temperature refrigerator, there are provided a pressure sensor (21) for detecting a pressure within a product vessel (20) of the air separating device (4) and a negative pressure sensor (16) for detecting a negative pressure within the insulated vessel (1) respectively. When at least one of both sensors (21) (16) detects a freezing of an impurity gas contained in the supplied nitrogen gas by reaching a predetermined pressure, an operation of the extremely low temperature refrigerator is stopped depending on the detection by one of both the sensors.

Abstract: A polyimide, and a gas separation membrane prepared therefrom, containing repeating units derived from 5(2,5-dioxo-tetrahydrofuryl)-3-methyl-3,3-cyclohexane-1,2-dicarboxylic anhydride is disclosed.

Abstract: Novel polyimide and polyamide-imide gas separation membranes and the process of using such membranes to separate one or more gases from a gaseous mixture is disclosed. The polyimides and polyamide-imides are formed from a blend of diamines containing the ester derived from 1,3-diamino-2-hydroxypropane.

Abstract: A process for inerting an interior of a container, the process comprising:(a) introducing an inert fluid rich stream into the interior of the container, the concentration of inert fluid in the inert fluid rich stream inert fluid being greater than the inert fluid concentration in the interior of the container;(b) increasing the concentration of inert fluid in the inert fluid rich stream during its introduction into the interior of the container; and(c) withdrawing or purging a waste gas stream containing at least one impurity and inert fluid from the interior of the container.

Abstract: The present invention provides a process for utilizing one stream from a gas separation unit in an evaporation cooler to provide cool water which is used to cool the feed gas mixture by direct or indirect contact prior to entering the gas separation unit.

Abstract: A membrane nitrogen gas generator, containing a feed stream compressor, one or more filtering membranes, each having a permeate side and a non-permeate side, in fluid connection with and downstream of the feed stream compressor, and one or more product storage containers capable of storing a product having a higher purity than is required by customer demand, and which generator is capable of generating an increased flow rate during periods of high demand.

Abstract: A membrane type oxygenator for effecting exchange of gases with a porous gas-exchange membrane possessing minute through pores forming a path for gas, which membrane type oxygenator is characterized by the fact that minute particles are retained in the minute pores of the porous gas-exchange membrane to permit a decrease in the cross-sectional area of the path for gas and as blood anticoagulant is retained in the minute particles or between the minute particles, and it is manufactured assembling a membrane type oxygenator containing a porous gas-exchange membrane possessing minute through pores forming a path for gas, then causing a dispersion of minute particles to flow through the interior of the membrane type oxygenator thereby allowing the minute pores to retain the minute particles and permitting a decrease in the cross-sectional area of the path for gas, removing the dispersion remaining within the membrane type oxygenator, and further causing a liquid containing a blood anticoagulant to flow through th

Abstract: A membrane gas generator, which contains: a) a feed stream compressor having a feed stream input, b) a heat source downstream of the feed stream compressor, and in fluid connection therewith, c) a heat accumulator downstream of the heat source, and in fluid connection therewith; and d) at least one membrane with a permeate side and a non-permeate side downstream of the heat accumulator.

Abstract: The invention provides carbon membranes for use in fluid separation processes, particularly gas separations, which are treated with a coating that provides a protective barrier which significantly limits permeation of water vapor or other impurities such as hydrocarbons without significantly inhibiting permeation of the faster fluid component or lowering selectivity. The composite membranes retain good fluid separation properties and are resistant to the adverse effects on membrane performance commonly observed in environments having high humidity. The coating is preferably an amorphous polymer of perfluoro-2,2-dimethyl-1,3-dioxole. The membranes can be of a varied configuration: sheet form, hollow fiber, asymmetrical membranes and the like.

Abstract: A process for generating a nitrogen-enriched gas from a feed stream of atmospheric air or a mixture of nitrogen which is not continuously supplied to a membrane system, which membrane system comprises a non-permeate side and a permeate side, and being more permeable to oxygen than nitrogen, which process entails feeding the feed stream side of the membrane, and recovering an oxygen enriched gas being recovered on the permeate side of the membrane system while a nitrogen-enriched gas is recovered from the non-permeate side of the membrane, wherein a feed back of nitrogen gas or nitrogen- containing gas having an oxygen gas concentration lower than 21% is supplied to the non-permeate side of the membrane system during at least a part of the period of time where the air feed stream is not supplied to the membrane system thereby avoiding any substantial retrodiffusion of oxygen through the membrane system from the permeate side to the non-permeate side of the membrane during those periods of time where the feed s

Abstract: The invention relates to the control of multistage fluid separation processes and systems. The processes and systems employ at least one recycle compressor or pump in conjunction with their associated controlling system to separate a fluid mixture in an efficient manner during off demand or turndown conditions. The operation of at least one recycle compressor or pump is controlled so as to maintain the pressure in the permeate side or sides at a set value, thus maintaining the desired pressure ratio across the multistage membrane and obtain the desired, reduced power consumption during off demand or turn-down conditions.

Abstract: The invention is a process for recovering oxygen from an oxygen-containing gaseous mixture containing one or more components selected from water, carbon dioxide or a volatile hydrocarbon which process utilizes ion transport membranes comprising a multicomponent metallic oxide containing barium. The process utilizes a temperature regime which overcomes problems associated with degradation of barium-containing multicomponent oxides caused by carbon dioxide.

Abstract: The present invention provides a process for dissolving oxygen comprising forming a liquid membrane of an oxygen-permeable liquid on a support layer made of a hydrophobic porous material, bringing one side of the liquid membrane into contact with an oxygen-containing gas and the other side with an aqueous liquor, and thereby dissolving oxygen in the aqueous liquor; a process for culturing cells in an oxygen-containing aqueous liquor obtained by the oxygen-dissolving process; and apparatus for practicing these processes. According to the present invention, oxygen can be dissolved in an aqueous liquor efficiently and economically, and aerobic cell-culturing can be stably effected even at a high cell concentration.

Abstract: The invention is a process for recovering oxygen from an oxygen-containing gaseous mixture containing one or more components selected from water, carbon dioxide or a volatile hydrocarbon which process utilizes ion transport membranes comprising a multicomponent metallic oxide containing strontium, calcium or magnesium. The process utilizes a temperature regime which overcomes problems associated with degradation of strontium-, calcium- and magnesium-containing multicomponent oxides caused by carbon dioxide.

Abstract: The present invention provides for gas separation membranes with superior gas transport properties made from a blend of certain polymers. In particular, certain alkyl substituted aromatic polyimides, polyamides or polyamide-imides are blended with certain aromatic polyimides to provide a gas separation membrane with superior productivity and good selectivity.

Abstract: The present invention relates to novel multi-layer composite solid state membranes which are capable of separating oxygen from oxygen-containing gaseous mixtures at elevated temperatures. The membranes comprise a multicomponent metallic oxide porous layer having an average pore radius of less than about 10 micrometers and a multicomponent metallic oxide dense layer having no connected through porosity wherein the porous and dense layers are contiguous and such layers conduct electrons and oxygen ions at operating temperatures.

Abstract: A cascade-sweep process is provided for producing nitrogen gas from air, using a plurality of stages of membrane units each containing a plurality of hollow fiber membranes, at least one of the plurality of membrane units containing a sweep input to inject a sweep gas longitudinally on the external surface of the hollow fiber membranes.

Abstract: This invention relates to a process for restoring permeance of an oxygen-permeable ion transport membrane utilized to recover oxygen from an oxygen-containing gaseous mixture which contains water, carbon dioxide or volatile hydrocarbons. The process utilizes a class of ion transport membranes formed from multicomponent metallic oxides wherein permeance of such membranes had been believed to be permanently degraded by water and the like under conventional process operating temperatures. This invention provides a continuous process for restoring oxygen permeance of such membranes caused by deleterious interaction between the membrane and components such as carbon dioxide, water or hydrocarbons at elevated process temperatures.

Abstract: .[.A process is provided for purifying argon gas, especially an argon gas stream obtained by cryogenically separating air, wherein the argon gas is heated and compressed, and then permeated through a solid electrolyte membrane selective to the permeation of oxygen over other components of the gas, and removing oxygen from the argon by selective permeation of oxygen through the membrane. The purified argon can then be distilled to remove other components such as nitrogen..]..Iadd.A process is provided for producing a purified argon stream wherein oxygen and nitrogen are removed from crude bulk argon streams, particularly those produced by cryogenic, adsorptive or membrane separation of air. The process comprises separating a heated, compressed crude argon stream containing nitrogen and oxygen into an oxygen permeate stream and an oxygen-depleted argon stream by passing the compressed heated argon stream through a solid electrolyte membrane selective to the permeation of oxygen.