Abstract: Adsorptive separation of carbon dioxide from a gaseous mixture comprising carbon dioxide and gases less polar than carbon dioxide comprising contacting the gaseous mixture with a zeolite adsorbent is effected wherein carbon dioxide present in the gaseous mixture as contacted with the zeolite has a partial pressure of 0.1 to 50 mmHg, and the zeolite adsorbent is a shaped product comprised of at least 95%, as determined in the basis of the moisture equilibrium adsorption value, of a low-silica type X zeolite having an SiO2/Al2O3 molar ratio of 1.9 to 2.1. Preferably, the zeolite adsorbent is preferably ion-exchanged with lithium and/or sodium, and is prepared by a process including a step of contacting with a caustic solution a calcined product of a mixture of a low-silica type X zeolite and kaolin clay whereby the kaolin clay is converted to a low-silica type X zeolite.

Abstract: A microelectromechanical gas concentrator is fabricated for extracting a gaseous component from a gas mixture. The gas concentrator consists of an adsorbent member that alternatively moves between two regions on a single substrate. When the adsorbent member is in the first region, it is allowed to adsorb the gaseous component. When the adsorbent member moves to the second region, it is exposed to radiant energy, causing it to desorb the gaseous component. As the adsorbent member moves alternatively between regions, the gaseous component is adsorbed by the adsorbent member in the first region and desorbed in the second region, resulting in a pumping action that concentrates the gaseous component from one region to the other.

Abstract: The present invention provides compact adsorption systems that are capable of rapid temperature swings and rapid cycling. Novel methods of thermal swing adsorption and thermally-enhanced pressure swing adsorption are also described. In some aspects of the invention, a gas is passed through the adsorbent thus allowing heat exchangers to be very close to all portions of the adsorbent and utilize less space. In another aspect, the adsorption media is selectively heated, thus reducing energy costs. Methods and systems for gas adsorption/desorption having improved energy efficiency with capability of short cycle times are also described. Advantages of the invention include the ability to use (typically) 30-100 times less adsorbent compared to conventional systems.

Abstract: An apparatus for treating exhaust gases. The apparatus includes an adsorbing tower containing an adsorbent to adsorb an impurity gas included in the exhaust gases. A desorbing tower heats the adsorbent to desorb the impurity gas from the adsorbent so that the adsorbent can be re-used. A transfer unit circulates the adsorbent between the adsorbing tower and the desorbing tower. A controller controls the temperature of the adsorbent. A helical heater is arranged in the desorbing tower to heat the adsorbent.

Abstract: The present invention provides compact adsorption systems that are capable of rapid temperature swings and rapid cycling. Novel methods of thermal swing adsorption and thermally-enhanced pressure swing adsorption are also described. In some aspects of the invention, a gas is passed through the adsorbent thus allowing heat exchangers to be very close to all portions of the adsorbent and utilize less space. In another aspect, the adsorption media is selectively heated, thus reducing energy costs. Methods and systems for gas adsorption/desorption having improved energy efficiency with capability of short cycle times are also described. In another aspect, the apparatus or methods utilize heat exchange channels of varying lengths that have volumes controlled to provide equal heat fluxes. Methods of fuel cell startup are also described. Advantages of the invention include the ability to use (typically) 30-100 times less adsorbent compared to conventional systems.

Abstract: A method and apparatus for controlling or removing mercury, mercury compounds and high molecular weight organics, if present, from a resource recovery exhaust stream by separately adding a carbonaceous char to the flue gas while it is still within the unit. The char can be produced in situ by adding a carbonaceous material and allowing it to thermally decompose.

Abstract: A method for purifying a minority constituent and concentrating it in a majority constituent of a gas mixture that also contains one or more other minority constituent(s) employs (i) a selective permeation step, (ii) next, a purification step, and (iii) finally a concentration step. In the selective permeation step, an initial gas mixture is passed through a membrane to yield a gas mixture that is enriched in the first minority constituent. In the purifying step, the first minority constituent is absorbed by a solid adsorbent which has a strong affinity for the first minority constituent, then following an elution step, a gas mixture that contains essentially only the majority constituent and the first minority constituent is formed.

Abstract: Nitrogen oxides and low molecular weight hydrocarbons are removed from air by subjecting the air to a temperature swing adsorption process using as the adsorbent a composite zeolite product containing both zeolite A and zeolite X. The composite zeolite product is preferably prepared by forming a mixture of an agglomerate of silica and sodium zeolite X having a Si/Al atomic ratio in the range of about 0.9 to less than about 1.2 and a water-soluble sodium aluminate salt; maintaining the mixture at a temperature in the range of about 25 to about 100° C. for a period of time sufficient to convert at least 50% of the silica to sodium zeolite A; and at least partially exchanging the zeolite A-containing product with divalent cations, preferably calcium ions.

Abstract: An aqueous solution with a pH of greater than 5, preferably of at least 6.5, can be used in an ion-exchange process, in particular a process for the manufacture of a zeolite. This aqueous solution comprises metal cations, such as zinc, and an agent for complexing the metal cations, such as citric acid or a salt of this acid. The proportion of free cations in solution represents from 0.1% to 99%, preferably from 1 to 30%, of the total amount of the metal in the solution. The invention also relates to a process for the manufacture of zeolites X or A employing such an aqueous solution and the use of the zeolites thus obtained for separating, purifying or converting one or more constituents of a gas stream, such as air, synthesis gases or hydrocarbons, in particular olefins, by employing an adsorption process, in particular a PSA, VSA or TSA.

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: A group of solid adsorbents in the form of powder, granules or pellets having improved adsorptive capacity and selectivity for ethylene and/or propylene is disclosed. These adsorbents comprise (a) a silver compound and (b) a bentonite clay support bulk of which comprises SiO2 and Al2O3 and the rest being oxides of Fe, Ca, Mg, Na and K and having sufficiently high surface area on which the silver compound is dispersed or impregnated. The support may be pretreated by polymer solutions to impart sufficient mechanical strength as measured by attrition loss. Mechanical strength may also be improved by pre-heating the support. These adsorbents are highly stable and are capable of reversibly adsorbing substantial quantity of ethylene and/or propylene at room temperature. The rates of adsorption of ethylene and/or propylene are also very high in these adsorbents, which is believed to be due to the synergistic interaction between the components of the novel composition of the present invention.

Abstract: The present invention provides a method and apparatus to purify various gases utilizing the superior performance a heated getter process in a smaller package than previous multiple stage, heated getter processes. The smaller package includes inner and outer enclosures, and an integral, regenerative heat exchanger to simultaneously increase heater efficiency and cool the purified gas. The invention also includes a particle filter to remove particles from the gas flow. The invention further provides an interface to various modular gas stick substrate designs with an inlet and an outlet in one end of the integrated heated getter purifier system. The inlet gas is preheated by the integral heat exchanger and then heated to operating temperature of 200-400° C. The heated getter removes various impurities from the gas. The heated gas is then cooled in the integral heat exchanger. The cooled gas is exposed to a second quantity of cooler getter to remove residual impurities.

Abstract: A gas separation process comprising feeding a gaseous mixture comprising at least two components having different adsorption characteristics into an adsorption vessel containing at least one adsorbent material capable of preferentially adsorbing at least one of the gaseous components in the gaseous mixture and subjecting the gaseous mixture to non-cryogenic conditions which enable the preferentially adsorbable gaseous component in the gaseous mixture to adsorb onto the adsorbent material and separate from the non-adsorbed component in the gaseous mixture which pass through the adsorbent vessel wherein at least one adsorbent material in the adsorbent vessel comprises a composite particle having an inner core comprising a non-porous, non-adsorbent material and at least one outer layer comprising the adsorbent material. In another embodiment of the process of the present invention a hollow particulate adsorbent material is utilized.

Abstract: A desorbable sorption filter, in particular for a heating or air-conditioning system of a motor vehicle, has a metallic support (12) which can be heated by flow of current and an adsorber (14) mounted at or on the support (12). To provide an improved, directly heatable sorption filter which particularly enables inexpensive production and good electrical and thermal conductive contact without the use of adhesives, it is proposed for the adsorber (14) to be of planar design and to be mechanically connected to the support (12, 112) by means of holding elements (26) formed integrally on the support (12, 112).

Abstract: A novel method and apparatus to dehumidify air provides enhanced dehumidification efficiency over conventional dehumidification apparatuses. A reusable dehumidification element disk provides a disk section to strip water from an air stream. The disk is rotated so that the saturated disk section enters a separate chamber where the water can be stripped from the disk with a stream of regeneration air. The regeneration air stream is recycled and is not split from or mixed with the air stream requiring dehumidification. The result is a more efficient dehumidification than in apparatuses which require the influent air stream to be divided into separate streams for dehumidification and regeneration functions.

Abstract: An assembly, a method and a motor vehicle for cleaning ambient air in the vicinity of an internal combustion engine (102) having combustion air inlet means (103) and energy emitting means (104)are disclosed. The assembly (101) further includes adsorbent means (105) for adsorbing at least one pollutant when in a first mode of operation and for desorbing the pollutant when in a second mode of operation. The adsorbent means have an inlet (106) for polluted ambient air (107, 107′) and an outlet (108) for cleaned ambient air (109, 109′). Furthermore, the assembly (101) includes a pollutant conduit (110) through which the desorbed pollutant is transferred from the adsorbent means (105) to the combustion air inlet means (103) when in the second mode of operation, and the adsorbent means (105) are arranged for being brought into the second mode of operation by means of energy supplied from the energy emitting means (104).

Abstract: A carbon fiber carbon matrix hybrid adsorbent monolith with enhanced thermal conductivity for storing and releasing gas through adsorption and desorption is disclosed. The heat of adsorption of the gas species being adsorbed is sufficiently large to cause hybrid monolith heating during adsorption and hybrid monolith cooling during desorption which significantly reduces the storage capacity of the hybrid monolith, or efficiency and economics of a gas separation process. The extent of this phenomenon depends, to a large extent, on the thermal conductivity of the adsorbent hybrid monolith. This invention is a hybrid version of a carbon fiber monolith, which offers significant enhancements to thermal conductivity and potential for improved gas separation and storage systems.

Abstract: A novel method and apparatus to dehumidify air provides enhanced dehumidification efficiency over conventional dehumidification apparatuses. A reusable dehumidification element disk provides a disk section to strip water from an air stream. The disk is rotated so that the saturated disk section enters a separate chamber where the water can be stripped from the disk with a stream of regeneration air. The regeneration air stream is recycled and is not split from or mixed with the air stream requiring dehumidification. The result is a more efficient dehumidification than in apparatuses which require the influent air stream to be divided into separate streams for dehumidification and regeneration functions.

Abstract: A method of treating a gaseous hydrocarbon contained in waste gas by using adsorbent layers of single-tower or multi-tower configuration is characterized in that (1) double-cylinder type or multi-cylinder type adsorption apparatus, in which each adsorbent layer is indirectly cooled by cooling water, are employed as adsorption apparatus; (2) each adsorbent layer is a packed layer of one or more kinds of materials selected from activated carbon, synthetic zeolites and hydrophobic silica gel; (3) swing time required for switching between adsorption and desorption processes is set to 1 to 15 minutes; (4) each adsorbent layer is evacuated under vacuum while being purged by using part of clean gas evacuated from each adsorbent layer and/or air in the desorption process; and (5) the gaseous hydrocarbon is recovered from outflow purge gas. This method makes it possible to prevent abnormal temperature increase within each adsorbent layer and enhance the safety of the apparatus.

Abstract: A process for regenerating an adsorber which adsorbs organic substances from the air in which the adsorber is heated by microwave energy to evaporate adsorbed organic substances on the adsorber. The adsorber is provided with enhanced microwave absorption capacity to enable the adsorber to evaporate the adsorbed organic substances. The adsorber can be produced to have itself high microwave energy absorbing capacity or a solid material can be combined with the adsorber to provide the high microwave absorbing capacity. The solid material can be combined with an adsorbing enhancing substance and can be a carrier therefor. In a particular embodiment, the adsorber can be a hydrophobic zeolite and the microwave absorbing material can be a hydrophilic zeolite.

Abstract: In accordance with the teachings of the present invention, an adsorbent filter having a continuous activated carbon fiber sheet is disclosed. The filter providing a frame, at least one continuous sheet of adsorbent fabric, and a plurality of supports for supporting the sheet within the frame such that contaminated fluid flows over one or more surfaces of the sheet. The contaminants being adsorbed by contact with the surface of the sheet.

Abstract: A process and device for scrubbing flows of gaseous effluents loaded with polluting substances, wherein the effluents are caused to circulate through a device including an array of scrubber units (4a to 4n) juxtaposed in an enclosure (3), each containing materials adsorbing the substances. When the adsorbing load thereof is saturated and for the scrubber units (4) to regain the scrubbing capacity thereof, they are selectively and successively isolated by a mobile collector (8) during the time required for their desorption by heating and for the substances to be transferred by an auxiliary fluid (a fraction of the circulating effluents for example or a gas delivered selectively to the inlet of the scrubber unit to be desorbed by an auxiliary circuit), and the substances mixed with the auxiliary fluid are possibly transferred towards a reactor (10) suited for removing them. The process can be applied for concentrating and scrubbing of polluting substances such as VOCs or gas dehumidification.

Abstract: An electrically regenerable gas filter system includes a carbon fiber composite molecular sieve (CFCMS) filter medium. After a separate medium-efficiency pre-filter removes particulate from the supply airstream, the CFCMS filter sorbs gaseous air pollutants before the air is recirculated to the space. When saturated, the CFCMS media is regenerated utilizing a low-voltage current that is caused to pass through the filter medium.

Abstract: A desiccant dehumidifier is provided in which a desiccant material is applied to a first end of a heat pipe heat exchanger. During the sorption phase, a supply air stream is exposed to the desiccant material on the first end of the heat pipe heat exchanger and a second air stream, which could be ambient atmosphere, is exposed to the second end of the heat pipe heat exchanger. The moisture from the supply air stream is transferred to the desiccant material. However, the heat pipe heat exchanger acts as a heat sink and adsorbs the heat generated by the moisture transfer and transfers it to the second end of the heat pipe heat exchanger. At the second end of the heat pipe heat exchanger, the heat is transferred to the second air stream. As a result, both the supply air stream and the desiccant material remain at a substantially constant temperature during the sorption phase.

Abstract: A pre-compression dehydration system optimizes the gas flow parameters which are essential to the performance of a radial or spherical desiccant dryer. When used in conjunction with a low pressure dryer, the system protects the desiccant bed from channeling, which can cause the gas to flow unevenly through the desiccant bed and fail to make effective contact with the desiccant. The system provides a multiple zone, or divided, desiccant bed adsorption unit to maintain a proper flow distribution as required by the demand of the air compressor and to eliminate the potential for channeling. The system may also include a controller for automatically opening and closing the port access doors of the adsorption unit to control the amount of desiccant utilized to dry the air. A thermostatically controlled precooler may be provided for cooling the ambient air prior to adsorption to insure that the temperature of the effluent air will not exceed 100.degree. F. (37.8.degree. C.

Abstract: A microtrap sample concentrator useful for concentrating a sample of purged gas containing analytes for delivery to an analytical instrument, including: a tube containing at least one sorbent material which retains or traps analytes; where greater than 30% of all trapped analytes are directly delivered to an analytical instrument at a desorption flow rate of one to three cc/min, without splitting or cryogenic focusing the trapped analytes; where delivery of the trapped analytes to the analytical instrument is achieved by passing the trapped analytes through a passage being selectively connectable between the microtrap and the analytical instrument, the passage connected to a vent; where the temperature of the passage is not lower than ambient room temperature; and where the passage is heated to a temperature sufficient to vaporize water in the passage and to expel the vaporized water out of the vent.

Abstract: An improved rotary concentrator separates the desorption gas flow into two flow portions. The first flow portion is sent to a final processing system. The second portion is recycled to the rotary concentrator. In a first embodiment, gas is recycled to the process gas inlet. In a second embodiment, the recycled gas is reused as desorption inlet gas. Most preferably, the recirculated gas is relatively clean compared to the gas in the first portion which is sent to the final processing system. In this way, the improved rotary concentrator is more efficient and reduces the amount of gas which must be processed by the final processing system.

Abstract: According to the invention, regeneration is performed by filtering and by regenerating simultaneously the used absorbent; two stages are carried out for the regeneration: one, which is a rough stage, is performed in the presence of a regeneration gas; the other, a free stage, is performed in the presence of a fresh regeneration gas.

Abstract: An air prepurification system which includes vertically oriented adsorption vessels containing, from top to bottom, a layer of moisture-selective adsorbent, a first layer of carbon dioxide-selective adsorbent and a second layer of carbon dioxide-selective adsorbent wherein the particle size of carbon dioxide-selective adsorbent in the second layer of carbon dioxide-selective adsorbent is smaller than the particle size of both the moisture-selective adsorbent and the carbon dioxide-selective adsorbent in the first layer of carbon dioxide-selective adsorbent. The air purification system is designed for use in a temperature swing adsorption process in which air is passed downwardly through the adsorption vessels during the adsorption step and upwardly through the vessels during the adsorbent regeneration step.

Abstract: Method to remove organic halogenated molecules from gaseous currents arriving as a residue of industrial working processes or not, the gaseous current being delivered into a reactor (16) containing a fluid bed consisting of at least one solid adsorbent element after having undergone at least one filtration followed by a cooling, the gaseous current cooperating with the solid particles with exchange by adsorption between the gaseous current and the solid particles, the reactor (16) achieving a time of contact between the gaseous current and the solid particles at least longer than 3 seconds, the gaseous current which enters the reactor (16) having a temperature lower than 80.degree. C., but advantageously between 30.degree. and 70.degree. C., the cooling of the gaseous current upstream of the reactor (16) being followed by a gas/water or gas/air heat exchanger (13).

Abstract: High purity argon is produced by subjecting a two-phase liquid-vapor mixture containing up to 3 volume % of nitrogen and/or up to 5 volume % oxygen to cryogenic temperature swing adsorption in an adsorption bed containing one or more adsorbents selective for nitrogen and/or oxygen at a temperature between the bubble point and the dew point of the two-phase mixture.

Abstract: In a pressure-swing adsorption-type gas separation unit, a distinct intermediate gas passageway is formed between a first water retaining bed (A) and a second separating adsorbent bed (B), a controlled heat flow being supplied to prevent the formation of a very cold area between both beds. The unit is particularly useful in the production of oxygen from air.

Abstract: A method and apparatus are provided for use in the delivery of an inhalation anesthetic to a patient while employing a closed loop or re-breather gas recirculation system. The method and apparatus control the system temperature to minimize heat buildup, including heat buildup resulting from an exothermic reaction between a patient's exhaled breath and a scrubbing substance that removes a selected constituent from the patient's exhaled breath. The apparatus includes an enclosure containing a scrubbing substance. The enclosure defines an influent opening for admitting the exhaled breath along a first path into the scrubbing substance and defines an effluent opening through which gases can be discharged from the enclosure. The apparatus also includes a second path adjacent the first path between inlet and outlet openings whereby a coolant fluid can flow along the second path to remove heat from the interior of the enclosure.

Abstract: A solvent fume exhaust scrubber (100) for recovering organic vapor from exhaust air which is produced during the manufacture of semiconductors includes a throttling chamber (180) containing a plurality of planar baffles (112, 114, 116, 118 and 120), a planar condenser (130) and a cooling coil (138) which engages and substantially traverses the planar surface of the condenser. The throttling chamber intersects an exhaust duct (152) so that an exhaust stream (182) flows in a flow direction (184) through the chamber. Each baffle and condenser has a planar surface which is disposed at right angles to the flow direction. The surface extends partially across the exhaust stream. The baffles are arranged sequentially along the flow direction and have offsetting planar surfaces across the exhaust stream so that the baffles in combination extend across the exhaust stream. A baffle includes a baffle frame (302) for holding a plurality of carbon beads (306).

Abstract: A process for removal and recovery of arsenic from a gas comprising contacting a supported sorbent with an arsenic-containing gas, adsorbing the arsenic with the supported sorbent, desorbing the arsenic from the supported sorbent, and collecting the desorbed arsenic.

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.