Abstract: The present invention is directed to a procedure for recycling used gasses and to devices that can be use to accomplish this recycling.

Abstract: A shaped zeolite-containing body, e.g., zeolite-containing monoliths, having high compressive strength is prepared from a particular class of siloxane-based binders in combination with zeolite, plasticizing agent, and methylcellulose. It has been discovered that when using the particular class of siloxane binder with the aforementioned components, the body formed therefrom can be processed and calcined at temperatures below 300° C., thereby reducing costs typically seen with other processes for preparing shaped materials containing zeolite. The shaped bodies of this invention have been shown to have compressive strengths of at least 20 N/mm2 or more.

Abstract: The present invention relates to a process for maintaining the humidity of an enclosed space within an acceptable operational range of relative humidity to minimize static electricity while passively removing at least a portion of organic contaminants from the enclosed space. The invention provides a simple, low cost solution to preventing damage to electronic disk drives using an adsorbent sheet material which requires less than about one-tenth the volume of adsorbent carriers which enclose the adsorbent material in a supporting envelope. The process employs a weak adsorbent such as high silica zeolite which effectively controls humidity at low operating temperatures and as the operating temperature increases is enabled to adsorb contaminants by reduced affinity for water.

Abstract: The present invention is a method for separating condensable substances from gases or gas mixtures with the use of porous materials including the steps of employing as adsorbents substances or materials suitable for capillary condensation and cyclically performing the method. The method can be used to separate water from air. The porous materials have a pore structure adapted to the environmental or climatic conditions present at the site of utilization of the method. The step of cyclically performing the method can be performing a plurality of times in succession separation by capillary condensation of the condensable substances in the porous materials and desorption of the condensed substances from the porous materials.

Abstract: The invention is concerned with a device and a process for drying air in ventilation devices for fuel tanks and gas drying in fuel tanks via vapor permeable membranes and sorbents.

Abstract: A process for the purification of a gaseous hydrogen flow containing one or more gaseous impurities from the group consisting of carbon monoxide, water vapor, nitrogen, H2S, chlorine, C1-C3 light alcohols, ammonia, carbon dioxide and linear, branched or cyclic hydrocarbons, saturated and unsaturated, C1-C8. The hydrogen flow is placed in contact with a porous carbonated adsorbent having an adsorption limit volume (W0) and an energy parameter of (E0) according to the Dubinin relationship, such that: 0.18 ml.g−1≦W0≦1.50 ml.g−1 and 15 kJ.mole−1≦E0≦45 kJ.mole−1. The porous carbonated adsorbent is selected from active carbons. The gas rich in hydrogen is a reforming gas, an electrolysis gas, a gas from ammonia cracking or from alcohol cracking.

Abstract: A process for purifying a gas stream containing at least one impurity chosen from the group formed by propane, nitrogen protoxide and ethylene, in which process: (a) the gas stream to be purified is brought into contact with at least one adsorbent including at least one X zeolite containing barium cations; (b) at least one impurity is adsorbed on the adsorbent. Preferably, the adsorbent includes particles of X zeolite exchanged to at least 70%, preferably at least 89%, with barium cations, it being possible for the adsorbent to furthermore include a bed of activated alumina particles which is located upstream of the bed of barium-exchanged X zeolite.

Abstract: Trace impurities such as organic compounds and carbon monoxide in reactive fluids such as ammonia, hydrogen chloride, hydrogen bromide, and chlorine are reduced to sub-ppb levels using gas purifying systems that contain a preconditioned ultra-low emission (P-ULE) carbon. P-ULE is capable of removing impurities from a reactive fluid down to parts-per-billion (ppb) and sub-ppb levels without concurrently emitting other impurities such as moisture or carbon dioxide into the purified reactive fluid. The P-ULE carbon is prepared by heating a carbon material to temperatures from 300° to about 800° C. in an ultra-dry, inert gas stream, to produce an ultra-low emission (ULE) carbon material, subjecting the ULE carbon to a second activation process under a reactive gas atmosphere to produce a P-ULE carbon and storing the P-ULE carbon in an environment that minimizes contamination of the P-ULE prior to its use in a gas purifier system.

Abstract: Desiccant tablets including solid potassium formate are used to dry gas, especially in natural gas transmission lines. Preferred tablets comprise 1-4% potassium formate (most preferably 2-3%), up to 1% of a surfactant as a lubricant, and the balance desiccant salts, preferably calcium chloride.

Abstract: Trace impurities such as organic compounds and carbon monoxide are reduced to sub-ppb levels in gases such as nitrogen, helium and argon, by gas purifying systems that contain an ultra-low emission (ULE) carbon material. Ultra-low emission (ULE) carbon materials can be made from commercially available carbon materials in the form of pellets, extrudates and beads and is capable of removing impurities from a gas stream down to parts-per-billion (ppb) and sub-ppb levels without concurrently emitting other impurities such as moisture or carbon dioxide to the purified gas stream. The carbon material is superactivated by heating the carbon to temperatures from 300° to about 800° degrees C. in an ultra-dry, inert gas stream. The ultra-low emission (ULE) carbon material is handled and stored in an environment that minimizes contamination from moisture and other oxygenated species in order to maintain its ppb and sub-ppb impurity removal and low emission properties.

Abstract: A method for recovering gasoline vapors in filling stations entails extracting the gasoline vapors during fuel delivery and dehumidifying the extracted vapors by passage through a cartridge which contains a dessiccant. The dehumidified vapors are then condensed into a liquid form by heat exchange with an intermediate fluid kept at the cooling temperature in contact with a heat exchanger through which a coolant flows. The liquid condensate is then separated and recovered and the appropriately treated and conditioned residual gaseous mixture is released into the atmosphere.

Abstract: The gas stream containing one or more gaseous impurities from the group formed by carbon dioxide, water vapor, H2S, alcohols, SO2 and C1-C8 saturated or unsaturated, linear, branched or cyclic hydrocarbons is brought into contact with several different porous carbon adsorbents, that is to say active carbons having different properties and characteristics. The gas is air, nitrogen, hydrogen produced by the reforming or cracking of ammonia or the combustion gas or fermentation gas.

Abstract: A method for removing trace moisture from a gas is disclosed. The method involves heating a zeolite having a high silica-to-alumina ratio to about 400° C. to remove physically adsorbed water from the zeolite, followed by heating the zeolite to a temperature in excess of 650° C., to form a superheated zeolite. The superheated zeolite is contacted with the gas, thereby adsorbing water from the gas. A dehydroxylated zeolite for removing trace moisture from a gas wherein the zeolite has a high silica-to-alumina ratio and a low level of metallic impurities is also disclosed. A method for removing metallic impurities from a gas using the low metals zeolite is also disclosed. The zeolites and methods of the invention are particularly useful for removing trace water and trace metal impurities from acid gases such as hydrogen chloride and hydrogen bromide.

Abstract: A method and composition for the removal of contaminants in a gas stream used in the contamination sensitive processes of photolithography and metrology are described. The synergistic effect of a combination of an electropositive metal component, a high silica zeolite, and a late transition metal compound effects removal or reduction of the contaminates in the gas which interfere with light transmittance to the ppb or ppt levels necessary for the gas to be suitable for these uses. The removal of neutral polar molecules, neutral polar aprotic molecules, protic and aprotic alkaline molecules, acidic polar species, and neutral non-polar aprotic molecules is accomplished with the claimed composition. Depending on the type of contaminant, the composition components are each varied from 10 to 80 parts by volume, with the total composition limited to 100 parts by volume.

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: In using partially alkali metal exchanged forms of FAU zeolite as selective adsorbents for use in insulated glass windows, particularly for use in a matrix in insulated glass windows, it has been discovered that significant reduction in the nitrogen loading on the zeolite results when the alkali metal content is maintained at a low level. For example, such FAU zeolites, particularly zeolite X which has been ion-exchanged with potassium ions to a level of between about 5 and about 75 equivalent mole percent indicate a nitrogen adsorption loading of between about 400 and 600 percent lower than unexchanged zeolite X and about 200 percent less than fully potassium exchanged zeolite X. The adsorbent is particularly useful in a sealant matrix for insulated glass windows and may be used in combination with zeolite A to reduce out-gassing problems.

Abstract: A process, especially a PSA or TSA process, for purifying a gas containing at least carbon dioxide (CO2) as impurity, in which the carbon dioxide is adsorbed on an adsorbent comprising particles of activated alumina. According to this process, the activated alumina has a specific surface area of between 200 m2/g and 299 m2/g and contains at least 80% aluminum oxide (Al2O3), silicon oxide (SiO2), iron oxide (Fe2O3) and from 0.001% to 7.25% of at least one oxide of at least one alkali or alkaline-earth metal, such as sodium and potassium oxides. According to the invention, the gas stream to be purified is air or a synthesis gas.

Abstract: Desiccant tablets including solid potassium formate are used to dry gas, especially in natural gas transmission lines. The most preferred tablets comprise 5-15% potassium formate, up to 1% of a surfactant as a lubricant, and the balance desiccant salts, preferably calcium chloride.

Abstract: A drying material disposed in the passage of a compressed air system for removing moisture from air or gas includes a plurality of semi-rigid porous substrates impregnated with lithium chloride. The drying material is formed by preparing a saturated solution of lithium chloride and a nonflammable solvent. Porous substrata are contacted with the saturated solution to wet the substrata surface. The wet substrata are heated at a sufficient temperature for a sufficient duration to drive off excess liquid from the substrate. A desiccant comprising lithium chloride impregnated substrata is produced.

Abstract: The present invention provides for a multi-composite adsorbent mixture which will remove H2O, CO2 and nitrogen oxides and/or hydrocarbons from a feed gas stream. The improvement lies in the use of a third adsorbent which is selective for nitrogen oxides, hydrocarbons or both.

Abstract: Desiccant tablets including solid potassium formate are used to dry gas, especially in natural gas transmission lines. The most preferred tablets comprise 5-15% potassium formate, up to 1% of a surfactant as a lubricant, and the balance desiccant salts, preferably calcium chloride.

Abstract: This invention provides a pressure swing adsorption process for purifying a synthesis gas stream containing from 60 to 90 mole % hydrogen and impurities such as CO2, CH4, N2, and CO. The PSA process of the invention further provides a method of adsorbing substantially all of the nitrogen and other contaminants from the feed gas stream; wherein the feed stream is passed at superatmospheric pressure through a plurality of adsorbent beds and each adsorbent bed contains at least a CaX, LiA, LiX or calcium containing mixed cation zeolite having a SiO2/Al2O3 mole ratio of 2.0-2.5. Such process involves sequentially pressurizing, depressurizing, purging and repressurizing the adsorbent beds with product hydrogen, and recovering product hydrogen in purities of 99.9% or greater from the beds.

Abstract: The present invention relates to method and apparatus for extracting water from atmospheric air. The method according to an embodiment of the invention does not depend on day and night temperature differentials and can operate at lower temperatures than were possible before. The present invention makes it possible to extract water vapors from the atmospheric air in relatively simple, inexpensive industrial plants or in smaller portable devices.

Abstract: A molecular sieve adsorbent for the purification of gas streams containing water vapor and carbon dioxide. The adsorbent is a combination of sodium form of a low-silica faujasite, having a residual content of potassium ions less than about 8.0 percent (equiv.), a low content of crystalline and amorphous admixtures and crystal sizes generally within the range of 1-4 &mgr;m, and a binder.

Abstract: A synthesis gas obtained by steam reforming is sent to a pressure swing adsorption unit (2) which separates a CO/H2 mixture, as a production gas, from the other constituents. The CO/H2 mixture is sent to a unit (3) for at least partially purifying CO, for example a permeation unit, which produces under pressure the CO with high purity or an H2/CO mixture with an adjusted CO content, containing very little impurities.

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 process is provided for the removal of trace amounts of aromatic hydrocarbons from an acid waste gas feed stream comprising sulfur compounds and the aromatic hydrocarbons. An adsorption process employing an adsorbent such as a high silica zeolite adsorbent having a framework silica-to-alumina ratio greater than about 15 and having a pore size greater than about 6.2 angstroms is used to remove from the feed gas mixture aromatic hydrocarbon contaminants and permit the recovery of a high purity sulfur product from the treated effluent stream. The use of the present invention removes aromatic hydrocarbon contaminants which are responsible for the degeneration of the performance of the downstream sulfur recovery zone.

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: The invention relates to a process for the purification of a gas stream containing one or more gaseous impurities from the group formed by carbon dioxide, water vapor, H2S, alcohols, S02 and C1-C8 saturated or unsaturated, linear, branched or cyclic hydrocarbons. The gas stream is brought into contact with several different porous carbon adsorbents, that is to say active carbons having different properties and characteristics. The gas is air, nitrogen, hydrogen produced by the reforming or cracking of ammonia or the cracking of alcohols or hydrocarbons, natural gas, combustion gas or fermentation gas.

Abstract: A process and apparatus for the decontamination of gaseous contaminants (especially oxygen, carbon dioxide and water vapor) from hydride gases (including their lower alkyl analogs) down to ≦100 ppb contaminant concentration are described. The critical component is a high surface area metal oxide substrate with reduced metal active sites, which in various physical forms is capable of decontaminating such gases to ≦100 ppb, ≦50 ppb or ≦10 ppb level without being detrimentally affected by the hydride gases. The surface area of the substrate will be ≧100 m2/g, and preferably 200-800 m2/g. Oxides of various metals, especially manganese or molybdenum, can be used, and mixtures of integrated oxides, or one type of oxide coated on another, may be used. The substrate is preferably retained in a hydride-gas-resistant container which is installed in a gas supply line, such as to a gas- or vapor-deposition manufacturing unit.

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 adsorbent and method for making it and its use in removing water from gaseous hydrogen halide. Magnesium halide supported on an activated carbon prepared under vacuum will remove water at 1 to 500 ppm.

Abstract: A device for continuously fractionating a gas by adsorption, an in-service testing device in a processor-controlled adsorption drier system and a method for testing the operating capability of an adsorption drier system under the control of a processor, including two adsorbent beds connected to one another in a switching system, in which regeneration is performed by a flow of regeneration gas. The device has a gas inlet, a gas outlet and a bypass outlet feeding into a common functional block, which contains a line switching circuit, a first and a second shuttle valve and, optionally, other components. The in-service testing device and the device are so compact due to their respective structures that they can be integrated with one another requiring little space and having low assembly requirements. The testing method is configured to co-operate with the in-service testing device and the device, requiring only a few components for the application thereof.

Abstract: A molecular sieve adsorbent for the purification of gas streams containing water vapor and carbon dioxide and a process for its preparation. The adsorbent is a sodium form of a low-silica faujasite having a silica to alumina ratio of about 1.8:1 to about 2.2:1, a residual content of potassium ions less than about 8.0 percent (equiv.), a low content of crystalline and amorphous admixtures and crystal sizes generally within the range of 1-4 &mgr;m, blended with a binder.

Abstract: A sample conditioning apparatus that removes moisture from a saturated gaseous sample and that utilizes the removed moisture for evaporative cooling within the apparatus is described. The sample conditioning apparatus includes a heat exchanger, a condensate drain trap, and a bypass line that directs a portion of the sample to a cooling medium inlet of the heat exchanger. The apparatus also includes a direction changing fitting to direct the condensate from the heat exchanger into a condensate drain trap. The direction changing fitting is coupled to a sample outlet of the heat exchanger and to the condensate drain trap. The direction changing fitting is also coupled to a membrane type moisture separator to prevent any liquid carrying over through to the gas analyzers. The moisture separator is also coupled to a first end of a bypass line, and to a sample line extending between the separator to the gas analyzers.

Abstract: Process and apparatus for the purification of a gaseous flow containing at least one impurity which can be carbon dioxide, water vapor and/or hydrocarbon. The impurity is adsorbed on a bed of adsorbent containing at least one adsorbent material, it being possible to use stacked adsorbent beds. Atop the uppermost bed is a layer of particulate ballast having a density greater than that of the adsorbent. The bed of ballast exerts a mechanical pressure on the subjacent adsorbent and prevents fluidization of the upper portion of the subjacent adsorbent. As a result, the rate of gas flow through the adsorbent can be increased.

Abstract: This invention is directed to the synthesis of high bulk density high gas absorption capacity adsorbents for gas storage applications. Specifically, this invention is concerned with novel gas absorbents with high gravimetric and volumetric gas adsorption capacities which are made from fullerene-based materials. By pressing fullerene powder into pellet form using a conventional press, then polymerizing it by subjecting the fullerene to high temperature and high inert gas pressure, the resulting fullerene-based materials have high bulk densities and high gas adsorption capacities. By pre-chemical modification or post-polymerization activation processes, the gas adsorption capacities of the fullerene-based adsorbents can be further enhanced. These materials are suitable for low pressure gas storage applications, such as oxygen storage for home oxygen therapy uses or on-board vehicle natural gas storage.

Abstract: A method for removing trace moisture from a gas is disclosed. The method involves heating a zeolite having a high silica-to-alumina ratio to about 400.degree. C. to remove physically absorbed water from the zeolite, followed by heating the zeolite to a temperature in excess of 650.degree. C., to form a superheated zeolite. Heating to temperatures of 650.degree. C. or above is believed to cause dehydroxylation of the zeolite. A method for the preparation of a dehydroxylated zeolite is also disclosed. The superheated zeolite is contacted with the gas, thereby adsorbing water from the gas. A dehydroxylated zeolite for removing trace moisture from a gas wherein the zeolite has a high silica-to-alumina ratio and a low level of metallic impurities is also disclosed. The zeolite and methods of the invention are particularly useful for removing trace water from acid gases such as hydrogen chloride and hydrogen bromide.

Abstract: Carbon dioxide, water, carbon monoxide and hydrogen are removed from a gas stream such as air or nitrogen by adsorbing water and carbon dioxide on a solid absorbent of alumina, or zeolite and oxiding carbon monoxide over a solid catalyst to carbon dioxide and adsorbing the resulting carbon dioxide and chemisorbing the hydrogen on the catalyst, which may be palladium on alumina.

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 process for fabricating a gas storage and dispensing system including a dispenser container for holding a physical sorbent material having sorptive affinity for (i) a sorbable dispensing gas to be held in and subsequently selectively discharged from the dispenser container, and (ii) extraneous sorbables, in which the physical sorbent material, having extraneous sorbables sorbed thereon, is treated to desorb from the sorbent material at least part of the extraneous sorbables, prior to loading the sorbent material into a gas storage and dispensing container.

Abstract: A method and apparatus for producing a clean dry air product stream. In accordance with the method and apparatus, a compressed feed air stream is introduced into one adsorption bed to adsorb moisture and carbon dioxide and to produce a first intermediate product stream. Impurities contained within the first intermediate product stream such as hydrocarbons, carbon monoxide and hydrogen are catalytically reacted to produce a second intermediate product stream that contains additional carbon dioxide and moisture produced from the catalytic reaction. The second intermediate product stream is introduced into another adsorption bed that adsorbs the additional moisture and carbon dioxide formed by the catalytic reaction to produce the clean dry air product stream. The present invention can be used alone to serve the need of supplying a clean dry air product stream. Additionally, it can be used as a prepurification unit of an air separation plant designed to produce an ultra-high purity industrial gas product.

Abstract: The present invention provides an air compressor which includes an air drier filled with a drying agent and having a first passage for supplying compressed air to one air supplied part while absorbing moisture from the compressed air by passing the compressed air through the drying agent (27) and a second passage (28a) for supplying the compressed air to another air supplied part without passing the compressed air through the drying agent. The air supplied through the first passage returns through the same passage to dry the drying agent.

Abstract: The production of naphtha gas from landfill gas is preferably accomplished through a gas purification step, a catalytic conversion of methane gas to hydrogen gas, and a blending step in which various process streams are blended to produce the naphtha gas stream. The landfill gas stream is first treated through a gas purification/separation procedure to produce a substantially pure methane stream. The purified methane stream is then split into at least two portions. The first portion is fed into a hydrogen reformer and a shift reactor, where the methane gas is converted into a hydrogen-bearing stream which includes hydrogen and carbon dioxide. The second portion of the stream is preferably fed into a mixer. In the mixer, the pure methane stream, the hydrogen-bearing stream and a portion of the purified landfill gas stream are preferably blended together to form a naphtha gas stream.

Abstract: Novel gas separation agents with precisely and predictably controlled pore sizes within the range of 3-4 Angstrom units and their preparation from ETS-4 by exchange with cations, particularly multivalent cations such as strontium followed by drying and calcination to effect controlled pore shrinkage is disclosed. These novel materials have utility in gas separation processes particularly the separation of nitrogen from a mixture of the same with methane.

Abstract: A sorptive article is provided. The sorptive article includes a polyolefin, a wax which is miscible with the polyolefin at the melt temperature of the polyolefin but phase separates on cooling of the article, and sorptive particles distributed in the article. Also provided is a method for removing moisture or other vaporous or liquid material from air or an object in the environment utilizing a novel sorptive article of the invention.

Abstract: A process, composition and apparatus for the removal of water from moist non-corrosive gases (such as those containing oxygen or CO.sub.2) down to .ltoreq.10-20 ppb water concentration are described. The dehydrating agent is an oxide or salt of an electropositive metal and has a surface area of at least 140 m.sup.2 /g, preferably 140-500 m.sup.2 /g, is compatible with the gas, and preferably is capable of dehydrating such gases to .ltoreq.1 ppb, preferably to as low as 500 ppt. The electropositive metal will be a Group 3b, 4b or lanthanide metal or vanadium. The preferred agent is a high surface area titania, zirconia, yttria or vanadia, with titania most preferred. The dehydrating agent can be in the form of a pelleted or granular bulk material or a coating on or within the pores of a substrate. The agent is retained in a simple container which is easily installed in a gas supply line for the gas, such as to a gas- or vapor-deposition manufacturing unit.

Abstract: A method is provided for removing water, carbon monoxide and carbon dioxide out of a gas, such as air, by passing the gas through a packed column so that the gas sequentially contacts a catalyst consisting of platinum or palladium and at least one member selected from the group consisting of iron, cobalt, nickel, manganese, copper, chromium, tin, lead and cerium wherein the catalyst is supported on alumina containing substantially no pores having pore diameters of 110 Angstroms or less under conditions which oxidize the carbon monoxide in the gas into carbon dioxide; an adsorbent selected from the group consisting of silica gel, activated alumina, zeolite and combinations thereof under conditions in which water is adsorbed and removed from the gas and an adsorbent selected from the group consisting of calcium ion exchanged A zeolite; calcium ion exchanged X zeolite; sodium ion exchanged X zeolite and mixtures thereof under conditions which carbon dioxide is adsorbed and removed from the gas.

Abstract: A gas sampling apparatus includes a probe tube having a tip positionable in a stream of products of combustion and a sample dryer tube connected in fluid communication with an end of the probe tube opposite the tip. The sample dryer tube is received in a purge gas tube along a lengthwise axis thereof. The purge gas tube and the sample dryer tube define therebetween a space through which a purge gas pump urges a purge gas in a first direction. A sample pump connected in fluid communication with the sample dryer tube urges therethrough in a second direction opposite the first direction a sample of gas obtained from the stream of products of combustion via the probe tube. A sensor is positioned to detect a constituent of the sample of gas exhausted from the sample dryer tube. The sample dryer tube is formed at least in part of a hydrophilic membrane and the purge gas entering the space contains less water vapor than the sample of gas.

Abstract: A process and composition for removing moisture from a NF.sub.3 or F.sub.2 gas wherein the gas is contacted with alumina particles coated with aluminum trifluoride. The aluminum trifluoride is formed by reacting alumina particles with an aqueous solution of hydrogen fluoride.