The invention relates to a process for recovering hydrogen (b) from crude gas (a) from a coke oven (110) in which the crude gas (a) produced in the coke oven (110) is initially compressed and in which impurities are subsequently removed from the crude gas (a) by pressure swing adsorption, wherein oxygen is depleted from the crude gas (a) using nonthermal plasma prior to the pressure swing adsorption, and to a plant for recovering hydrogen from crude gas.

An exhaust system for the treatment of an exhaust gas comprising a species to be treated, the system comprising: a first gas inlet for providing a flow of exhaust gas; a second gas inlet for providing a flow of heated gas; a plurality of sorbent beds for releasably storing the species; one or more catalysts for decomposing the species; first and second exhaust gas outlets; and a valve system configured to establish independently for each sorbent bed fluid communication in a first or second configuration, wherein: i) in the first configuration the flow of the exhaust gas from the first gas inlet contacts a sorbent bed for storing the species and then passes to the first gas outlet; and ii) in the second configuration the flow of heated gas from the second gas inlet contacts a sorbent bed for releasing the species, passes to one of the one or more catalysts and then passes to the second exhaust gas outlet; wherein the valve system is configured to ensure that at least one sorbent bed is in the first configuration and, preferably at least one other sorbent bed is in the second configuration.

Organic sulfur compounds contained in refinery off gas streams having either high or low concentrations of olefins are converted to hydrogen sulfides which can be then be removed using conventional amine treating systems. The process uses a catalytic reactor with or without a hydrotreater depending on the olefin concentration of the off gas stream. The catalytic reactor operates in a hydrogenation mode or an oxidation mode to convert a majority of organic sulfur compounds into hydrogen sulfides.

An air purifier includes a reactor having a hollow shape extending in a first direction, a first purifying portion disposed inside the reactor in a fixed manner, where the first purifying portion has a facing surface perpendicular to the first direction, and includes an adsorbent for adsorbing a pollutant inflowing into the reactor and a first catalytic oxidant for removing a desorbed pollutant, and a heating portion disposed opposite to the facing surface, where the heating portion applies heat to a partial area of the first purifying portion, and is movable with respect to the first purifying portion along a plane perpendicular to the first direction.

Organic sulfur compounds contained in refinery off gas streams having either high ort low concentrations of olefins are converted to hydrogen sulfides which can be then be removed using conventional amine treating systems. The process uses a catalytic reactor with or without a hydrotreater depending on the olefin concentration of the off gas stream. The catalytic reactor operates in a hydrogenation mode or an oxidation mode to convert a majority of organic sulfur compounds into hydrogen sulfides.

A built-in apparatus and method for treating air including a housing with an air inlet and an air outlet. An air mover positioned near the air outlet is configured to draw the air through the air inlet. The housing encloses an air treatment zone, such as including an oxidizing zone, and an ozone removal zone positioned downstream of the air treatment zone and oxidizing zone. The air treatment zone includes UV light and/or ozone that partially oxidizes the chemical contaminants in the air treatment zone. A catalyst in the oxidizing zone oxidizes elements within the air treatment zone. The ozone removal zone includes a second, different catalyst material. A UV bulb that may or may not generate ozone is positioned within or downstream of the first and/or second catalyst materials to assist catalyst oxidation and/or self-clean the apparatus.

Disclosed herein is a system for the removal of volatile organic compounds, carbon monoxide and nitrogen oxides from off-gas even at high NO.sub.2 to NO.sub.x ratios, wherein the amount of NO.sub.2 within NO.sub.x is higher than or equal to 50 mol-%, comprising a source of ammonia, means for introducing ammonia into a catalytic article having an SCR functionality; a catalytic article having both an oxidation and an SCR functionality, the catalytic article comprising a catalyst substrate and a catalyst composition comprising at least one platinum group metal and/or at least one platinum group metal oxide, at least one oxide of titanium and at least one oxide of vanadium, wherein the washcoat is located in and/or on the walls of the catalyst substrate: means for measuring the amount of NO.sub.x and/or the ammonia slip between the outlet end of the catalytic article and the stack or at the stack, at least one carbon monoxide source, and means for introducing carbon monoxide into the catalytic article. Optionally, an SCR catalytic article can be placed upstream of downstream of the cata-lytic article having both an oxidation and an SCR functionality. Also disclosed is a method for the removal of volatile organic compounds, carbon monoxide and nitrogen oxides from off-gas introducing carbon monoxide in order to keep the amount of NOx and/or the ammonia slip between the outlet end of the catalytic article and the stack or at the stack at predetermined values. The method makes use of the system according to the invention. The system and the method can be used for the cleaning of flue gas.

A counter-current cross-flow heat exchanger for heating a first gas and cooling a second gas, includes modules in fluid communication with one another, each module being positioned on a plane, the planes mutually overlapping. Conduits allow entry and exit of the first and second gases into and out of the exchanger. Each module has heat exchange plates, with heating and cooling faces. The plates are orthogonal to the module plane and parallel to define alternating heating and cooling spaces. The first gas crosses each heating space with a direction substantially parallel to the plane of each module and the second gas crosses each cooling space with a direction substantially orthogonal to the plane of each module. The cooling spaces between adjacent modules are in direct fluid communication. The heating spaces between adjacent modules are in fluid communication with one another by conduits/conveyors, creating a serpentine path.

The invention relates to an apparatus (1) for catalytic decomposition of nitrous oxide in a gas stream derived from exhalation air from a patient. The apparatus (1) comprises an inlet arrangement (2) with a gas inlet (3) for the exhalation air, an outlet arrangement (11) with a gas outlet (12) for an outlet gas, and between these arrangements a through-flow decomposition chamber (9) containing a catalyst material. According to the invention the apparatus is provided with a nitrous oxide adsorption/desorption means (4) in the inlet arrangement (2) for level out variations in the concentration of nitrous oxide fed to the decomposition chamber (9).

A compact, lightweight, low power aircraft air filtration and VOC removal unit enables the removal of VOCs from cabin air in a passenger aircraft. A plurality of baffles having air flow-through airflow spaces are spaced apart along a duct. UV LEDs are mounted on the interior sides of the outermost baffles, and on both sides of all interior baffles. A filter module is disposed between pairs of baffles, and spaced from the baffles sufficiently to illuminate the entirety of both sides. Each filter modules comprises a plurality of filters. The filters are selected from a coarse foam, a fine foam, or a fused quartz filament felt. Each filter is loaded with a catalyst including one or more of AEROXIDE® P25, other pure titanium dioxide (TiO.sub.2), iron-doped TiO.sub.2, carbon-doped TiO.sub.2, and combinations thereof. The catalysts on the filters, under UV illumination, chemically reduce VOCs in the airflow to non-VOC molecules.