Abstract: The present invention provides a combination filter for filtering fluids comprising a flow channel particulate filtration media having a first face and a second face and a gas adsorbing filtration media. The flow channel particulate filtration media comprises a plurality of flow channels directed in flow direction and defined by inner surfaces. The flow channels having inlet openings through the first face and outlet openings through the second face of the flow channel particulate filtration media. The inner surfaces of said flow channels at least in part are provided with structures protruding therefrom and forming or extending into the flow channels or an electrical charge or a combination of both. The said gas adsorbing filtration media comprises a pad having a first face and a second face and width and length dimensions orthogonal with respect to each other and each individually to the flow direction and having a thickness dimension in flow direction.

Abstract: A method of separating a gas mixture using a permeation membrane unit, wherein the gas mixture, containing primarily hydrogen and carbon monoxide, is first treated to reduce the level of secondary components to lower than 100 molar ppm.

Abstract: Colloidal crystalline molecular sieve seeds are used in phosphorus-containing crystalline molecular sieve manufacture. Certain of the products have enhanced utility in oxygenate conversions.

Abstract: An oil separator for oil-flooded rotary vane vacuum pumps has a filter housing (10) and a plurality of filter cartridges (14) disposed therein through which the pumping medium flows. The filter cartridges (14) are each inserted through a respective opening (16) in an outer housing wall (12) of the filter housing (10) and are secured to the housing wall (12) so as to be detachable and tight with respect to media.

Abstract: A regenerable adsorber for removing VOCs from gas streams consists of a porous monolithic carbon which can be regenerated by heating by passing an electric current through it.

Abstract: Carbon dioxide is purified through the use of catalytic oxidation. Carbon dioxide is exposed to at least one catalyst, oxidizing at least a portion of the nonvolatile organic residues to form purified carbon dioxide that is directed to an application. Carbon dioxide that is in a near-critical, critical, or supercritical phase can be exposed to the catalyst.

Abstract: A method and mobile system for cleaning dirty gas from a newly stimulated gas well. The entire system is supported on a trailer or other mobile support so that it can be driven from well site to well site for short-term, post-stimulation use only. The system comprises a gas separator, such as a membrane separator. The system also includes a pretreatment assembly for preparing the gas for the gas separator. The pretreatment assembly may include separators, a heater, a guard vessel and a polishing filter. A chiller or heat exchanger cools the treated gas to a marketable temperature. A generator and a hydraulics plant provide power to the system. Each mobile system will be designed to treat gases with widely different operating conditions varying from well to well.

Abstract: A Process for the production and uses of a molecular sieve adsorbent blend product with improved performance characteristics produced by preparing a zeolite powder, preparing a highly dispersed attapulgite fiber binder, mixing the zeolite powder with the highly dispersed attapulgite binder to form a mixture, forming molecular sieve adsorbent products into a shaped material and calcining the shaped material, wherein the tapped bulk density of the highly dispersed attapulgite fibers measured according to DIN/ISO 787 is more than about 550 g/ml.

Abstract: A filter such as an air having a reagent which chemically reacts with and removes a gaseous component of an air stream. The reagent contains functional groups covalently bonded to a non-volatile inorganic substrate which is incorporated in the filter. The filter can remove gaseous components such as aldehydes. Preferred functional groups are 3-aminopropylsilyl groups covalently bonded to silica gel (APS silica gel). The reagent can be contained in a space in the filter or incorporated in one or more filter elements. The reagent can be part of or coated on paper such as filter paper or incorporated in non-paper filter elements formed from fibrous materials such as cellulose acetate or polypropylene fibers. Other preferred reagents include aminoethylaminopropylsilyl silica gel (AEAPS) and aminoethylaminoethylaminopropylsilyl silica gel (AEAEAPS).

Abstract: A method and apparatus for preventing contamination of a substrate or a substrate surface, and particularly relates to prevention of contamination of raw materials, semi-finished products, base materials of products and substrate surface in a high-tech industry such as an in the production of semiconductors and liquid crystals. A gas coming into contact with a base material or substrate is purified by dust removing apparatus and adsorption and/or absorption apparatus so that the concentration of fine particles in the gas is below class 1,000 and a non-methane hydrocarbon concentration is below 0.2 ppm. Thereafter, the base material or the substrate surface is exposed to this gas.

Abstract: A fluid purifying apparatus that includes a manifold that includes a first branch and a second branch, a first check valve coupled to the first branch of the manifold, and a purifier unit that includes a first end and a second end, wherein the first end is coupled to the second branch of the manifold. Also, a fluid purifying apparatus that includes a vessel that includes a first interior compartment for containing a purifier material and a second interior compartment for containment of a fluid containing impurities, wherein the first interior compartment is separated from the second interior compartment by a fluid permeable support, and a rupturable seal.

Abstract: A gas adsorption composite a high density adsorbent including a high density layer having a first density of at least 0.3 g/cc; and a low density adsorbent having a low density layer having a second density of less than 0.3 g/cc, wherein the high density adsorbent is in substantially contiguous contact with the low density adsorbent and each of the high density adsorbent and the low density adsorbent has an adsorbent surface area of at least 500 m2/g. A pressure swing adsorption process for recovering a product gas from a feed gas, the process including supplying a pressure swing adsorption apparatus including a gas adsorption composite, feeding a feed gas into the pressure swing adsorption apparatus during a feed period not exceeding 100 seconds and recovering the product gas from the pressure swing adsorption apparatus.

Abstract: An adsorbent includes core particles containing an adsorbing material; a porous coating layer including a polymer material that coats the core particles; and an underlying layer containing a metal compound and disposed between the core particles and the porous coating layer. The porous coating layer is formed by spraying and applying a suspension or a solution containing the polymer material over the adsorbing material, or by immersing the adsorbing material into the suspension or the solution.

Abstract: The invention is directed to a process for the adsorption of organic vapours from gas mixtures containing them onto activated carbon, where the process comprises passing the gas mixture consecutively through at least a first and a second adsorption system, the first system consisting of activated carbon having a first adsorption rate for the organic vapours and the second system consisting of an adsorbent having a second adsorption rate for the organic vapours, the second adsorption rate being higher than the first adsorption rate, more in particular to such process when used in the operation of vehicle internal combustion engines.

Abstract: An adsorbent composition containing a modified carbonaceous material capable of adsorbing an adsorbate is disclosed, wherein at least one organic group is attached to the carbonaceous material. Furthermore, methods to increase the adsorption capacity of a carbonaceous material capable of adsorbing an adsorbate and methods to adsorb an adsorbate using the above-described adsorbent composition are also disclosed.

Abstract: Conducting a PSA process for the purification of gaseous hydrogen contaminated at least with CO and N2 of the H1 where the gas stream to be purified is passed through an adsorption region comprising at least one adsorbent based on zeolite 5A and one adsorbent based on zeolite X exchanged with calcium.

Abstract: A process for removal of ethylene oxide (EO) from ambient air laden with EO is passed through a zeolite-based removal media, which preferrably consists of the acid form of zeolite ZSM-5, herein referred to as “H-ZSM-5.” The process described herein may be applied to many forms, configurations and uses, such as, for example, gas masks, fume hood ventilation filters, cartridge filters, etc. Preferably, the H-ZSM-5 is configured within an apparatus in such a manner that the stream containing EO is brought into sufficient contact with the zeolite to remove the EO from the airstream.

Abstract: An apparatus and a method for purifying the air used in cryogenic air separation are described, which are capable of effectively removing nitrogen oxides and/or hydrocarbons. The apparatus comprises an adsorber comprising an adsorption cylinder that has a first adsorbing layer and a second adsorbing layer therein. The first adsorbing layer is composed of a first adsorbent capable of selectively adsorbing water in the air. The second adsorbing layer is composed of a second adsorbent capable of selectively adsorbing nitrogen oxide and/or hydrocarbon in the air passing the first adsorbing layer, wherein the second adsorbent comprises an X zeolite containing magnesium ion as an ion-exchangeable cation.

Abstract: A process for removal of ethylene oxide (EO) from ambient air laden with EO is passed through a zeolite-based removal media, which preferrably consists of the acid form of zeolite ZSM-5, herein referred to as “H-ZSM-5.” The process described herein may be applied to many forms, configurations and uses, such as, for example, gas masks, fume hood ventilation filters, cartridge filters, etc. Preferably, the H-ZSM-5 is configured within an apparatus in such a manner that the stream containing EO is brought into sufficient contact with the zeolite to remove the EO from the airstream.

Abstract: An auxiliary fuel vapor adsorption device includes a housing and an activated carbon segment contained within the housing and including a quantity of activated carbon material. A dust separator is also contained within the housing and in fluid communication with the carbon segment, and a canister vent valve is mounted to the housing in fluid communication with the activated carbon segment. The invention allows for the reduction of evaporative emissions by minimizing interconnecting joints between necessary fuel system components.

Abstract: A method for efficiently removing vapor-phase contaminants from gas streams is described. A powdered adsorbent such as activated carbon is ground into a fine powder by wet grinding to form a slurry. Chemicals are added to the slurry to impregnate the sorbent to enhance sorbent effectiveness. The slurry chemical mixture is sprayed into the gas stream in the form of small droplets which evaporate to produce an aerosol of fine adsorbent particles. Vapor-phase contaminants in the gas stream adsorb onto the fine adsorbent particle surfaces and the adsorbent particles are removed from the gas stream by a conventional particle collection method.

Abstract: The present invention describes a pressure swing adsorption (PSA) apparatus and process for the production of purified hydrogen from a feed gas stream containing heavy hydrocarbons (i.e., hydrocarbons having at least six carbons). The apparatus comprises at least one bed containing at least three layers. The layered adsorption zone contains a feed end with a low surface area adsorbent (20 to 400 m2/g) which comprises 2 to 20% of the total bed length followed by a layer of an intermediate surface area adsorbent (425 to 800 m2/g) which comprises 25 to 40% of the total bed length and a final layer of high surface area adsorbent (825 to 2000 m2/g) which comprises 40 to 78% of the total bed length.

Abstract: Inorganic, porous particles filter a substance or substances from a flow of fluid such as a gas. The particles can be arranged into a bed to filter a substance (filtrate substance) from a fluid. The filtrate substance can collect on or within the pores of the inorganic particles. Collection of the filtrate substance within the pores of the particles rather than within the interstices of the bed enhances the filtering capacity and does not impede the flow of fluid through the bed of particles. Furthermore, the inorganic particles are re-usable, in that they can be subjected to harsh filtrate-separation techniques, e.g., heat treatment, solvent extraction, detergent washing, and centrifugal separation, yet retain their desired properties.

Abstract: A material for fixing gaseous hydrocarbon containing fibrous crystal aggregates formed by precipitating by making a metal aliphatic carboxylate dissolve completely in pure water to give a solution, stirring and gradually cooling the resulting solution; a method of preparing the fixing material; and a method of adsorbing and solidifying gaseous hydrocarbon by using the fixing material.

Abstract: A method and apparatus of the invention includes a method of removing airborne hydrocarbons from liquid electrophotographic printer exhaust comprises generating airborne hydrocarbon droplets as either vapor or mist during the transportation of electrophotographic ink or toner, directing substantially all of the air and hydrocarbon droplet mixture to a central collection point, forcing the air/droplet mixture to and through an oleophilic, substantially non-leaching collection media, and exhausting substantially hydrocarbon-free air from the electrophotographic printer. The method may further comprise inducing pressure in the printer with air pressure reduction to pull the exhaust through the collection media, for example with a pump or fan used to produce air pressure reduction. The method may comprise inducing airflow in the printer with ventilation holes or by the addition of a fan to provide a fresh air inlet. The air/hydrocarbon mixture may be directed to the collection media by a transportation system.

Abstract: A gas separation module includes an adsorbent filter medium inside the case that holds the active gas separation membrane. The adsorbent filter is positioned upstream of the membrane and is operative to extract from the feed gas contaminants which adversely affect membrane separation performance and which if not removed, would cause the membrane separation performance to deteriorate. The adsorbent filter fits within vacant space in conventionally-sized hollow fiber membrane modules and thus can obviate the need to install an external adsorbent filter upstream of the module and/or to enlarge the space occupied by the module to accommodate addition of the internal adsorbent medium.

Abstract: A fluid storage and dispensing apparatus, including a fluid storage and dispensing vessel having an interior volume, in which the interior volume contains a physical adsorbent sorptively retaining a fluid thereon and from which the fluid is desorbable for dispensing from the vessel, and a dispensing assembly coupled to the vessel for dispensing desorbed fluid from the vessel. The physical adsorbent includes a monolithic carbon physical adsorbent that is characterized by at least one of the following characteristics: (a) a fill density measured for arsine gas at 25° C. and pressure of 650 torr that is greater than 400 grams arsine per liter of adsorbent; (b) at least 30% of overall porosity of the adsorbent including slit-shaped pores having a size in a range of from about 0.3 to about 0.72 nanometer, and at least 20% of the overall porosity including micropores of diameter <2 nanometers; and (c) having been formed by pyrolysis and optional activation, at temperature(s) below 1000° C.

Abstract: The present invention provides a method for removing hydrocarbons from an exhaust gas of an internal combustion engine. The method of the present invention comprises contacting the exhaust gas with a water-removing composition and then contacting the exhaust gas at a position downstream from the water-removing composition with a hydrocarbon-removing material to remove at least some of the hydrocarbons from the exhaust gas. The hydrocarbon-removing material use in the present invention has a sufficiently low Si to Al atom ratio that less than 50% of the low molecular hydrocarbons desorb from the hydrocarbon-removing composition at a temperature of 250° C.

Abstract: A method and apparatus for preventing contamination of a substrate or a substrate surface, and particularly relates to prevention of contamination of raw materials, semi-finished products, base materials of products and substrate surface in a high-tech industry such as in the production of semiconductors and liquid crystals. A gas coming into contact with a base material or substrate is purified by dust removing apparatus and adsorption and/or absorption apparatus so that the concentration of fine particles in the gas is below class 1,000 and a non-methane hydrocarbon concentration is below 0.2 ppm. Thereafter, the base material or the substrate surface is exposed to this gas.

Abstract: The present invention is a process for separating propylene and dimethylether from a mixture comprising propylene, dimethylether, and propane. The mixture is passed through a bed of an adsorbent comprising a porous crystalline material having (i) diffusion time constants for dimethylether and propylene of at least 0.1 sec−1, and (ii) a diffusion time constant for propane of than 0.02 of the diffusion time constants for dimethylether and propylene. The bed preferentially adsorbs propylene and dimethylether from the mixture. The adsorbed propylene and dimethylether are then desorbed from the bed.

Abstract: A method and apparatus of the invention includes a method of removing airborne hydrocarbons from liquid electrophotographic printer exhaust comprises generating airborne hydrocarbon droplets as either vapor or mist during the transportation of electrophotographic ink or toner, directing substantially all of the air and hydrocarbon droplet mixture to a central collection point, forcing the air/droplet mixture to and through an oleophilic, substantially non-leaching collection media, and exhausting substantially hydrocarbon-free air from the electrophotographic printer. The method may further comprise inducing pressure in the printer with air pressure reduction to pull the exhaust through the collection media, for example with a pump or fan used to produce air pressure reduction. The method may comprise inducing airflow in the printer with ventilation holes or by the addition of a fan to provide a fresh air inlet. The air/hydrocarbon mixture may be directed to the collection media by a transportation system.

Abstract: Oil entrained in purge air from a vehicle air dryer is directed through a purge air cleaner to remove the oil before discharge of the purge air to the environment. An absorbent material, perferably hydrophobic, is enclosed in the purge air cleaner, which may be safely disposed. Alternatively, oil can be extracted from the absorbent media and thereby recycled. By providing a spin-on type canister, the absorbent media can be easily replaced and serviced.

Abstract: A filter assembly includes a shaped adsorbent article disposed in a housing. The shaped adsorbent article has one or more projections extending from a surface of the article toward the housing to provide for flow of fluid between the shaped adsorbent article and the housing. The filter assembly may optionally include a diffusion channel for additional filtering and/or one or more porous polymer films disposed over inlet or outlet openings in the housing to reduce or prevent particulate contamination. The filter assembly may be used in a device, such as a computer disk drive, to filter a fluid, such as air, within and/or entering or exiting the device.

Abstract: A method for removing a first sorbate having a first desorption activation energy and a second sorbate having a second desorption activation energy from a sorbent, involves a two-stage desorber. In a first stage, the first sorbate, second sorbate and the sorbent are contacted with a stripping fluid having a first temperature sufficient to separate the first sorbate in a vapor phase from the sorbent. In a second stage, the second sorbate and the sorbent is heated to a second temperature higher than the first temperature to separate the second sorbate in a vapor phase from the sorbent. The second sorbate can then be condensed to a liquid phase and sold to offset the costs of the process. Heating in the second phase can be facilitated by the introduction of microwave or infrared energy for stripping the second sorbate from the sorbent. Use of the microwave or infrared energy can be facilitated with a purging gas which can also be heated to function as a stripping gas.

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° C. 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: An air cleaner assembly for an internal combustion engine and process for eliminating fuel emissions from passing into the atmosphere. The air cleaner assembly includes a housing comprising a filter element situated therein, an outlet, and an inlet; and an adsorber panel disposed within the housing, wherein the adsorber panel comprises a pollutant treating material and a substrate.

Abstract: A process for removing at least water and carbon dioxide from a feed gas stream of air, synthesis gas or natural gas is described, comprising the steps of: contacting the feed gas stream with a composite adsorbent comprising silica and metal oxide, wherein the composite adsorbent contains at least 50 wt % silica, to form a first purified gas stream, and regenerating the composite adsorbent at a temperature of 0 to 200° C. The process optionally further comprises contacting the first purified gas stream with a carbon dioxide adsorbent and/or a nitrous oxide or hydrocarbon adsorbent.

Abstract: The trend in personal and light commercial transportation vehicle choices is heading toward electric or fuel cell vehicles capable of zero emission. Their demand for electricity to re-charge batteries or hydrogen to operate fuel cells can best be met by onsite production of electricity and hydrogen from conventional transportation fuel by an on-site energy supply system employing a conversion device. This approach can result in minimum changes in the present day infrastructure of the automobile and truck service station industry and can avoid any disturbances to the normal operation of the electric power industry. The onsite hydrogen/electricity hybrid conversion device is a reformer and/or a fuel cell. The output of the system can be varied to either meet the demand of hydrogen fuel for fuel cell vehicles or to provide electricity for charging batteries used on the electrical vehicles.

Abstract: A process is described for the manufacture of crystalline molecular sieve layers with good para-xylene over meta-xylene selectivity's good para-xylene permeances and selectivities. The process requires impregnation of the support prior to hydrothermal synthesis using the seeded method and may be undertaken with pre-impregnation masking. The crystalline molecular sieve layer has a selectivity (&agr;x) for para-xylene over meta-xylene of 2 or greater and a permeance (Qx) for para-xylene of 3.27×10−8 mole(px)/m2.s.Pa(px) or greater measured at a temperature of ≧250° C. and an aromatic hydrocarbon partial pressure of ≧10×103 Pa.

Abstract: In a process for separating propylene and dimethylether from a mixture comprising propylene, dimethylether, and propane, the mixture is passed through a bed of an adsorbent comprising a porous crystalline material having (i) diffusion time constants for dimethylether and propylene of at least 0.1 sec−1, when measured at a temperature of 373° K and dimethylether and propylene partial pressures of 8 kPa, and (ii) a diffusion time constant for propane, when measured at a temperature of 373° K and a propane partial pressure of 8 kPa, less than 0.02 of said diffusion time constants for dimethylether and propylene. The bed preferentially adsorbs propylene and dimethylether from the mixture. The adsorbed propylene and dimethylether are then desorbed from the bed either by lowering the pressure or raising the temperature of the bed.

Abstract: Methods for regenerating activated carbon mainly used in air-treating devices in transportation, in particular for passenger compartments in transportation conveyances. The invention can be also used for regenerating activated carbon for air-treating devices in other areas. The method for regeneration of activated carbon comprises a regeneration, which is performed with the help of water vapor obtained from condensate of humidity in the atmosphere. The condensate is pre-adsorbed on silica gel during air cleaning. The regeneration is carried out at the atmospheric pressure, at a temperature of up to 160° C. followed by cooling with the help of the fan with an air flow of no less than 25 min−1.

Abstract: Disclosed are a carbon dioxide purification process and apparatus including (i) an adsorbing step for removing a predetermined amount of hydrocarbons from a carbon dioxide feed gas to reduce the caloric value of the feed stream, and (ii) a catalytic oxidation step located downstream of the adsorbing step for removing residual hydrocarbons from the feed gas by catalytic oxidation.

Abstract: Compositions and methods for destroying chemical and biological agents such as toxins and bacteria are provided wherein the substance to be destroyed is contacted with finely divided metal oxide nanoparticles. The metal oxide nanoparticles are coated with a material selected from the group consisting of surfactants, waxes, oils, silyls, synthetic and natural polymers, resins, and mixtures thereof. The coatings are selected for their tendency to exclude water while not excluding the target compound or adsorbates. The desired metal oxide nanoparticles can be pressed into pellets for use when a powder is not feasible. Preferred metal oxides for the methods include MgO, SrO, BaO, CaO, TiO2, ZrO2, FeO, V2O3, V2O5, Mn2O3, Fe2O3, NiO, CuO, Al2O3, SiO2, ZnO, Ag2O, the corresponding hydroxides of the foregoing, and mixtures thereof.

Abstract: A pressure swing adsorption process for recovering a product gas from a feed gas, includes: supplying a pressure swing adsorption apparatus including an adsorbent composition containing activated carbon as a major ingredient, wherein the adsorbent composition and the apparatus are substantially free of zeolite adsorbents; feeding a feed gas into the pressure swing adsorption apparatus during a feed period not exceeding 20 seconds; and recovering the product gas from the pressure swing adsorption apparatus. The process and apparatus are particularly suitable for use with fuel cells and other applications requiring compact, rapid cycling systems for producing high purity hydrogen.

Abstract: A process for removing at least water and carbon dioxide from a feed gas stream of air, synthesis gas or natural gas is described, comprising the steps of:

Abstract: This invention relates to a process for separating a fluid component from a fluid mixture comprising the fluid component, the process comprising: (A) flowing the fluid mixture into a microchannel separator; the microchannel separator comprising a plurality of process microchannels containing a sorption medium, a header and a footer, the combined internal volume of the header and the footer being up to about 40% of the internal volume of the process microchannels; the fluid mixture being maintained in the microchannel separator until at least part of the fluid component is sorbed by the sorption medium; purging the microchannel separator to displace non-sorbed parts of the fluid mixture from the microchannel separator; and (B) desorbing the fluid component from the sorption medium and flowing a flush fluid through the microchannel separator to displace the desorbed fluid component from the microchannel separator. The process is suitable for purifying oxygen as well as effecting other fluid separations.

Abstract: A process is described for the elimination of hydrogen sulfide from gas mixtures by catalytic oxidation over activated carbon catalyst which converts the hydrogen sulfide to elemental sulfur and water, the former being sorbed by the activated carbon while the latter is transported with the gas mixture and may be removed by known dehydration processes. The above oxidative process is conducted at elevated temperatures and pressures and with sufficient residence time to assure virtually complete conversion of the hydrogen sulfide with minimal production of by-product sulfur dioxide. Traces of heavy hydrocarbons in the feed gas mixture which may reduce the life of the catalyst and the quality of the sulfur product may be removed by cryogenic means or by sorption on an activated carbon guard bed.

Abstract: An adsorbent article having a base body or matrix onto which is applied an adsorptive coating. The body or matrix can be a honeycomb matrix or structure having a plurality of cells defining a plurality of passages extending through the body. The adsorptive coating comprises an adsorptive media, such as activated carbon or ion exchange resin, that is bound by a polymeric adhesive or resin. The adsorbent article has a minimal pressure loss therethrough.

Abstract: An adsorbent for a hydrocarbon, comprising a calcined &bgr;-type zeolite showing a powder X-ray diffraction such that the sum of X-ray diffraction intensities at lattice spacings d=1.15±0.03 nm and d=0.397±0.01 nm, is at least 90% of the diffraction intensity at d=0.346±0.01 nm of Catalysis Society reference catalyst JRC-Z-HM-20(3).

Abstract: A natural gas engine capable of exhaust emission control over the entire temperature range and at low costs without requiring a complicated structure. An adsorbent (7) is disposed between a fuel tank (4) and a fuel supply port (5) on a suction air passage (2), and NMOG in the fuel gas supplied to the fuel tank (4) is adsorbed by the adsorbent (7) to purify the fuel gas in advance. When the temperature of a catalyst (11) disposed on an exhaust passage (3) reaches an activation temperature, the adsorbent (7) is heated by a heater (9) to a desorption temperature to desorb NMOG from the adsorbent (7) and purify the NMOG by the catalyst (11).