Abstract: A pressure swing adsorption apparatus for producing a gas mixture with a higher concentration of a particular gas such as oxygen from ambient air, in which the noisier components of the apparatus are contained in an internal removable module that is separated by sound insulation from the balance the apparatus to attenuate structure borne vibration, reduce radiated noise, and to absorb airborne sound.

Abstract: An adsorbent and a process are disclosed for drying gases in a pressure swing dryer. The adsorbent comprises a pre-formed alumina particle having a surface area of about 250 to 550 m2 &mgr;g with a thin layer of colloidal silica disbursed on the surface of the pre-formed alumina particle. Surprisingly the thin layer of colloidal silica does not interfere with the drying properties of the pre-formed alumina particle, while significantly improving the physical properties of the pre-formed alumina particle.

Abstract: An air dryer and reservoir assembly for providing compressed air from an air compressor (20) on a heavy motor vehicle which includes an air dryer (14) connected to receive compressed air from the air compressor (20) and a secondary reservoir (12), including an integral purge volume (34), for storing compressed air which passes through the air dryer (14), with the air dryer (14) and the secondary reservoir (12) being securely attached to a housing (16) to form an air dryer reservoir module (10). A primary reservoir (18) for storing compressed air from the air dryer (14) is located remote from the air dryer reservoir module (10). A pressure equalizing mechanism (57) is disposed between the primary reservoir (18) and the secondary reservoir (12) for keeping pressure in the two reservoirs (12,18) equal.

Abstract: For a single chamber air drier in a compressed air system on a vehicle the volume of dry regeneration air required to regenerate a desiccant in the air drier has to be determined. This can be accomplished in that data regarding system pressure, outdoor temperature and supplied air volume are continuously provided to a compute, which in relation to these parameters controls the supply of regeneration air to the air drier.

Abstract: A method and system for climate control uses a desiccant in an automobile. The desiccant removes humidity or moisture from air passing through the ventilation system. The desiccant is recharged or dried by application of a vacuum. The lower pressure generated by the vacuum reduces the temperature at which water evaporates or boils off of the desiccant material.

Abstract: A method of separating a first gaseous component from a gas mixture comprising a first gaseous component and a second gaseous component comprising passing the gaseous mixture into an adsorption zone containing an adsorbent material capable of preferentially adsorbing at least one of the gaseous components in the gaseous mixture, to separate the first gaseous component from the second gaseous component wherein the adsorbent material is a monolithic wheel having a plurality of channels throughout, the channels being aligned parallel to the direction of flow of the gaseous mixture and having a wall thickness of less than 1 mm and recovering the non-preferentially adsorbed gaseous component from the adsorption zone. Preferably, the adsorption zone comprises multiple layers of monolithic structures in the shape of a wheel stacked one upon the other in a direction parallel to the direction of the flow of the gaseous mixture and formed by spirally winding a sheet of corrugated adsorbable material about a hub.

Abstract: The present invention provides a method and apparatus for extracting liquid water from moist air using minimal energy input. The method can be considered as four phases: (1) adsorbing water from air into a desiccant, (2) isolating the water-laden desiccant from the air source, (3) desorbing water as vapor from the desiccant into a chamber, and (4) isolating the desiccant from the chamber, and compressing the vapor in the chamber to form liquid condensate. The liquid condensate can be removed for use. Careful design of the dead volumes and pressure balances can minimize the energy required. The dried air can be exchanged for fresh moist air and the process repeated. An apparatus comprises a first chamber in fluid communication with a desiccant, and having ports to intake moist air and exhaust dried air. The apparatus also comprises a second chamber in fluid communication with the desiccant. The second chamber allows variable internal pressure, and has a port for removal of liquid condensate.

Abstract: The present invention provides a method and apparatus for extracting liquid water from moist air using minimal energy input. The method can be considered as four phases: (1) adsorbing water from air into a desiccant, (2) isolating the water-laden desiccant from the air source, (3) desorbing water as vapor from the desiccant into a chamber, and (4) isolating the desiccant from the chamber, and compressing the vapor in the chamber to form liquid condensate. The liquid condensate can be removed for use. Careful design of the dead volumes and pressure balances can minimize the energy required. The dried air can be exchanged for fresh moist air and the process repeated. An apparatus comprises a first chamber in fluid communication with a desiccant, and having ports to intake moist air and exhaust dried air. The apparatus also comprises a second chamber in fluid communication with the desiccant. The second chamber allows variable internal pressure, and has a port for removal of liquid condensate.

Abstract: The present invention provides for methods and compositions for gas separation and purification utilizing a metallo-organic polymer adsorbent in processes for separating carbon dioxide, water, nitrogen oxides and hydrocarbons from gas streams.

Abstract: A heat exchanger, perhaps a cross flow heat exchanger, has first and second passages. During dehumidification (adsorption of moisture) in the first passages, water is evaporated from the second passages. This water can be introduced to the second passages during reactivation (desorption of moisture) in the first passages or at another time. If the water is introduced to the second passages during reactivation, the first and second passages have therein first and second moisture adsorbents. During a first time period, air to be dehumidified is passed through the first passages of the heat exchanger and cooling air is passed through the second passages of the heat exchanger to remove heat generated in the first passages and to desorb moisture adsorbed by the second moisture adsorbent. During a second time period, a heating fluid is passed through the second passages of the heat exchanger to heat the first passages and supply moisture for adsorption to the second moisture adsorbent.

Abstract: A pressure swing adsorption process includes providing a pressure swing adsorption apparatus having six beds, and equalizing a pressure of each of the six beds in four steps, wherein at all times during the process, at least one of the six beds is providing offgas. The process is particularly suitable for purifying hydrogen from a feed gas mixture containing hydrogen and at least one of methane, carbon dioxide, carbon monoxide, nitrogen and water vapor.

Abstract: Improved methods for the controlled generation of ammonia from an ammoniated metal salt at substantially ambient temperature by applying microwave energy to the salt. The ammoniated salts have the formula MAn·(NH3), wherein M is at least one metal selected from the group consisting of alkali metals, alkaline earth metals, scandium, ytterbium, the lanthanides, titanium, zirconium, hafnium, vanadium, niobium, tantalum, chromium, molybdenum, tungsten, manganese, technetium, rhenium, iron, ruthenium, osmium, cobalt, rhodium, iridium, nickel, palladium, platinum, copper, silver, gold, zinc, cadmium, mercury, tin, and aluminum; A is at least one ion selected from the group consisting Cl−, Br−, F−, I−, ClO3−, ClO4−, BF4−, AlCl4−, PF6−, SbCl6−, and SbF6−; and SbF6− n is from 1 to 6; and X is from 1 to 8.

Abstract: An air dryer system for a trailer braking assembly is modified to provide a purge flow when the park brakes are actuated. An air reservoir, either the main air tank or a separate reservoir, is in operative communication with the trailer air dryer. A valve disposed at a supply end of the trailer air dryer selectively vents a purge flow to atmosphere in response to a park brake application. A restricting orifice limits the purge flow through the trailer air dryer to extend the purge time and maximize the removal of moisture from the air dryer.

Abstract: A monolithic hygroscopic material shaped to facilitate a circulation flow of ambient air. The hygroscopic material may be used to remove various compounds from an ambient gas and may be reactivated to restore its drying capacity. The tendency of the material to seek equilibrium may be utilized to achieve dehumidification or humidification.

Abstract: A gas separation device includes an inner conduit, and a concentric outer conduit. An electrically conductive filter media, preferably a carbon fiber composite molecular sieve, is provided in the annular space between the inner conduit and the outer conduit. Gas flows through the inner conduit and the annular space between the inner conduit and the outer conduit, so as to contact the filter media. The filter media preferentially adsorbs at least one constituent of the gas stream. The filter media is regenerated by causing an electric current to flow through the filter media. The inner conduit and outer conduit are preferably electrically conductive whereby the regeneration of the filter media can be electrically stimulated. The invention is particularly useful for the removal of CO2 from the exhaust gases of fossil-fueled power plants.

Abstract: Adsorption of carbon dioxide from gas streams at temperatures in the range of 300 to 500° C. is carried out with a solid adsorbent containing magnesium oxide, preferably promoted with an alkali metal carbonate or bicarbonate so that the atomic ratio of alkali metal to magnesium is in the range of 0.006 to 2.60. Preferred adsorbents are made from the precipitate formed on addition of alkali metal and carbonate ions to an aqueous solution of a magnesium salt. Atomic ratios of alkali metal to magnesium can be adjusted by washing the precipitate with water. Low surface area adsorbents can be made by dehydration and CO2 removal of magnesium hydroxycarbonate, with or without alkali metal promotion. The process is especially valuable in pressure swing adsorption operations.

Abstract: A hygroscopic material having at least one passageway or channel therethrough. In a dehumidifier embodiment, the material is shaped to provide a surface area to facilitate gas flow, and drying of an ambient gas by creating a chimney effect which facilitates mixing of the gas. This causes the heavier water vapor or other compound containing gas to contact adsorbent material adjacent to the passageway or channel, adsorb at least some of the compound, and cause the lighter gas to exit the passageway or channel. The dehumidifier may have various shapes and sizes and can be reactivated to restore its drying capacity. When utilized as a humidifier, the material desorbs or adds the constituent (such as water vapor) to the gas and a downdraft rather than a chimney effect is achieved.

Abstract: Improved methods for the controlled generation of ammonia from an ammoniated metal salt at substantially ambient temperature by applying microwave energy to the salt. The ammoniated salts have the formula MAn.X(NH3), wherein M is at least one metal selected from the group consisting of alkali metals, alkaline earth metals, scandium, ytterbium, the lanthanides, titanium, zirconium, hafnium, vanadium, niobium, tantalum, chromium, molybdenum, tungsten, manganese, technetium, rhenium, iron, ruthenium, osmium, cobalt, rhodium, iridium, nickel, palladium, platinum, copper, silver, gold, zinc, cadmium, mercury, tin, and aluminum; A is at least one ion selected from the group consisting Cl−, Br−, F−, I−, ClO3−, ClO4−, BF4−, AlCl4−, PF6−, SbCl6−, and SbF6−; and SbF6− n is from 1 to 6; and X is from 1 to 8.

Abstract: A method and device for drying a gas by means of adsorption on a desiccant able to be regenerated (11), whereby a portion of the dried gas is used for regenerating the desiccant. The gas portion used for the regeneration is heated in at least two successive steps, said steps being performed in different zones (30,31 or 33-36) situated successively in the flow direction of the gas portion through the regenerating desiccant (11) and by stopping the heating in a zone (30,31 or 33-36) as soon as the desiccant (11) in this zone (30,31 or 33-36) is regenerated, so that this zone (30,31 or 33-36) may already cool down by the gas portion for regeneration while a successive zone (30,31 or 33-36) is still regenerated by the heated gas. In each vessel (7, 8) at least two individually controllable heating elements (25-26; 27-28; 38-41) are present.

Abstract: An apparatus and method of use for effectively purging desiccant air dryers of moisture load by introducing heated purge air into the containment vessel holding the desiccant, directly into those areas of the desiccant bed where the moisture loads are most heavily saturated. The improved heat regenerated desiccant gas dryer utilizes parallel ports for introducing heated air or an internal heat distributor, the former automatically controlled by valves selectively operated to allow purge air to quickly cause water vapor adsorbed by the desiccant to be released and discharged from the vessel, allowing the dryer to be returned to service in the gas drying mode with greater confidence that undesirable dew point spikes have been eliminated. More efficient use of heated purging air enables shorter turn-around times for the dryer and energy savings.

Abstract: A method of processing semiconductor manufacturing exhaust gases for recovering at least hexafluoroethane in which a feed stream composed of the exhaust gases is passed through an adsorbent bed selected to adsorb oxygen, and also nitrogen if present, but not to appreciably adsorb the hexafluoroethane. As a result, a product stream, discharged from the adsorbent bed, has a higher concentration of hexafluoroethane than in the feed stream. In one embodiment, only a single adsorbent such as carbon molecular sieve is provided to adsorb the oxygen or a modified 4A zeolite could be used to adsorb both oxygen and nitrogen. When nitrogen is a potential constituent, layers of carbon molecular sieve and zeolite are provided to adsorb the oxygen and then the nitrogen, respectively. A third adsorbent, preferably 5A zeolite may be provided in addition to the foregoing two adsorbents to also adsorb any carbon tetrafluoride produced as a by-product.

Abstract: A gas phase adsorption process in which a gas phase containing water vapor or a basic gas is brought into contact with activated carbon fiber to adsorb the water vapor or basic gas. The activated carbon fiber comprises pitch-based oxidized activated carbon fiber having oxygen-containing functional groups and an oxygen content of 3-18% by weight, based on the weight of the fiber. The oxidized activated carbon fiber is prepared by oxidizing pitch-based activated carbon fiber having a specific surface area of 200-2500 m.sup.2 /g.

Abstract: A pressure swing adsorber (PSA) air prepurifier includes at least a first adsorber and a second adsorber and a controller for controlling air feed to the first adsorber and the second adsorber. The invention is a "realtime" method for controlling cycle times for each adsorber and includes the following steps. During a determined time period, flow is measured to an adsorber that is coupled to an air inlet. An actual totalized flow to the on-line adsorber is accumulated, based upon the measured flow values. During this time, air feed conditions (e.g., temperature, pressure, relative humidity) are monitored and periodically, a maximum totalized flow to the adsorber is calculated, determined, at least in part, based upon the monitored air feed conditions.

Abstract: Process and apparatus for the purification of a cryogenic fluid in liquid, diphase, gaseous or supercritical state, having boiling point Pe, with at least one of its impurities having a boiling point Pe', with Pe'>Pe. The process includes at least one step selected from the group comprised by:a filtration step of at least one impurity in solid state,and an adsorption step of at least one impurity in liquid or gaseous state;and in which there is recovered at least one portion of the cryogenic fluid at least partially purified.

Abstract: An apparatus for providing oxygen-enriched air at a first pressure and at a second pressure, the second pressure being greater than the first pressure. The apparatus comprises, in combination, a pressure swing adsorption system and a pressure intensifier. The pressure swing adsorption system for enriching the oxygen content of air has a pressure of at least the first pressure. The pressure swing adsorption system is adapted to provide oxygen-enriched air to a first outlet at the first pressure and to provide oxygen-enriched air to a pressure intensifier at the first pressure. The pressure intensifier pressurizes the oxygen-enriched air and provides the oxygen-enriched air to a second outlet at the second pressure.

Abstract: A process for the adsorption of at least carbon dioxide, water and oxides of nitrogen and preferably acetylene from a feed gas, comprises contacting the feed gas with an adsorbent mixture of a zeolite and an alumina. The process may be operated as a swing adsorption process comprising contacting the gas with the adsorbent at a first temperature and pressure to adsorb at least carbon dioxide, water and oxides of nitrogen therefrom and periodically regenerating the adsorbent by reducing the pressure and or increasing the temperature to which the adsorbent is exposed.

Abstract: The invention comprises a PSA gas prepurifier for the removal of contaminants present in a feed gas stream. The prepurifier of the invention has a bed of adsorbent material which comprises at least two discrete layers of adsorbents, at least one of the adsorbents being comparatively strong and at least another of the adsorbents being comparatively weak.

Abstract: A pressure swing process for air separation to produce concentrated gaseous oxygen at an elevated pressure without the requirement of further compression of the gaseous oxygen product. The process comprises the steps of compressing the feed air to a pressure in the range of approximately 45 psig to 105 psig, preheating the feed air to each of the adsorption beds to a temperature in the range of approximately 100.degree. F. to 200.degree. F., then directing flow of the feed air cyclically into and through at least two crystalline zeolite molecular sieve adsorption beds for selectively adsorbing at least nitrogen therein. In this manner, oxygen having a purity of approximately 88% to 93% at a recovery of approximately 30% to 45% and a bed size factor in the range of 2,500 pounds to 4,000 pounds of adsorbent per ton per day of oxygen can be delivered to a receptor tank at an elevated pressure of approximately 40 psig to 100 psig.

Abstract: A process for the production of hydrogen that purifies a synthesis gas stream, containing hydrogen, carbon monoxide and combustibles, in a PSA unit. The PSA unit produces at least three streams: a substantially pure hydrogen product stream, a combustible-rich first tail-gas stream, and a carbon dioxide-rich second tail gas stream.

Abstract: A method and apparatus for the purification and collection of hydrogen isotopes in a flowing inert gaseous mixture containing impurities, wherein metal alloy getters having the capability of sorbing non-hydrogen impurities such as oxygen, carbon dioxide, carbon monoxide, methane, ammonia, nitrogen and water vapor are utilized to purify the gaseous mixture of impurities. After purification hydrogen isotopes may be more efficiently collected. A plurality of parallel process lines utilizing metal getter alloys can be used to provide for the continuous purification and collection of the hydrogen isotopes.

Abstract: An apparatus capable of providing rapid cooling and/or freezing comprises a cabinet or container having a cooling chamber, one or more reactors each containing a complex compound formed by adsorbing a polar gas on a metal salt, in which the polar gas is alternately adsorbed and desorbed on the complex compound, and in which the complex compound is formed by restricting the volumetric expansion and controlling the density during adsorption of the polar gas on the metal salt, whereby the complex compound is capable of adsorbing said polar gas at a rate of greater than 15 moles per mole hour of the complex compound in about 20 minutes or less, a condenser for condensing the polar gas, an evaporator thermally exposed to the cooling chamber for providing cooling therein, and conduits and one or more valves for directing said polar gas from the one or more reactors to the condenser, from the condenser to the evaporator and from the evaporator to the one or more reactors.

Abstract: An apparatus capable of providing rapid cooling and/or freezing comprises a cabinet or container having a cooling chamber, one or more reactors each containing a complex compound formed by adsorbing a polar gas on a metal salt, in which the polar gas is alternately adsorbed and desorbed on the complex compound, and in which the complex compound is formed by restricting the volumetric expansion and controlling the density during adsorption of the polar gas on the metal salt, whereby the complex compound is capable of adsorbing said polar gas at a rate of greater than 15 moles per mole hour of the complex compound in about 20 minutes or less, a condenser for condensing the polar gas, an evaporator thermally exposed to the cooling chamber for providing cooling therein, and conduits and one or more valves for directing said polar gas from the one or more reactors to the condenser, from the condenser to the evaporator and from the evaporator to the one or more reactors.

Abstract: A method for the removal from a feed gas stream such as air of at least two contaminating gas components such as water and CO.sub.2 features repeated cycles of operation the improvement which comprise: feeding a regenerating gas such as dry nitrogen at a higher temperature, e.g. 70.degree. C., in a direction counter-current to the feed direction in contact with the adsorbent to produce a heat pulse travelling in the counter-current direction to desorb the less strongly adsorbed second contaminating gas component from the downstream (with respect to the feed direction) portion of the adsorbent by TSA while at the same time desorbing the more strongly adsorbed second contaminating gas component from the upstream (with respect to the feed direction) portion of the adsorbent by PSA.

Abstract: In an aircraft, a pressure swing adsorption system (23) is used both for removing carbon dioxide and water vapour from recycled cabin air and for producing in an emergency oxygen from pressurized engine bleed air.

Abstract: A gas mixture comprised of nitric oxide and, optionally an inert gas, and containing small amounts of nitrogen dioxide, and perhaps moisture and sulfur dioxide, is purified by passing the gas stream through a bed of metal cation-free silica, alumina, or zeolite. The concentration of nitrogen dioxide, sulfur dioxide and moisture in the gas stream are significantly reduced as the gas mixture passes through the bed of adsorbent.

Abstract: A process for restarting an adsorption receptacle which is part of an installation for the purification of hydrogen by pressure swing adsorption (PSA), which receptacle, during a hiatus in its operation, has been depressurized and then rendered inert with nitrogen. The receptacle is repressurized with practically pure hydrogen, and then the adsorption cycle is restarted in this receptacle. The repressurization is effected counter-current with respect to the adsorption direction in the receptacle. The receptacle is repressurized with hydrogen produced by the installation before the hiatus. The process can be used for the treatment of a catalytic hydrocarbon reforming gas, in which case the receptacle contains successively, in the adsorption direction, a layer of alumina, a layer of carbon and a layer of molecular sieve.

Abstract: To recover liquid methane from a feed gas mixture (1) essentially consisting of methane, C.sub.2+ hydrocarbons, carbon dioxide and nitrogen, the feed gas mixture (1) is fed first to an adsorption unit (E) and freed from water; dried feed gas mixture (2) is fed to a membrane separating unit (F), wherein the carbon dioxide is separated down to a residual content less than 2% by volume (9) and resultant gas mixture (3) now essentially consisting of methane, C.sub.2+ hydrocarbons and nitrogen is fed to a low-temperature distillation (A) wherein the C.sub.2+ hydrocarbons as well as the residual content of carbon dioxide are separated by distillation.

Abstract: The present invention relates to a controlled process for producing amorphous, microporous silica gels having a predetermined water sorption isotherm of moderate Type I shape having a separation factor between about 0.07 and 0.1 and micropore diameter size between about 6 and 8.7 angstroms. The present microporous silica gels are prepared by adjusting the pH of the reaction system or by doping the system with various elements during the hydrolysis and condensation of alkoxy silicates to form silica gels therefrom, and the hydrolyzed products are successively polymerized to form polymers and particles containing siloxane bonds as follows: ##STR1## Various factors, for example open vs closed system, amount of water used for hydrolysis, type of alkoxides and solvent, pH, amount of catalyst, temperature, aging and drying conditions etc., affect the nature and the rate of hydrolysis, condensation reactions and network formation, and consequently the properties of the final gel products.

Abstract: A process and system for pressurizing a vessel for integrity testing with gas comprising helium, recovering the gas comprising helium, and purifying the gas comprising helium for reuse. The process for purifying the gas stream comprising helium comprises drying the gas stream; separating the dried gas stream in a membrane separator stage into a helium-enriched permeate product stream and a helium-depleted raffinate stream; recovering helium in the raffinate stream in a membrane stripper stage thereby producing a purge stream; and purging water from the dryer with the purge stream.

Abstract: Reaction rates in chemisorption reactions involving solid reactants and gaseous ligands are improved by maintaining optimized solid density throughout the reaction. Methods and apparatus which restrict volumetric solid expansion, compression of the solid reactant, and mixture with inert solid porous or particulate materials are disclosed.