Through the procedures of pretreatment, temperature swing adsorption (TSA) coarse desorption, pressure swing adsorption (PSA) purification and hydrogen purification, the hydrogenous waste gas from various procedures in the manufacturing process of semiconductor (especially silicon wafer), including the off-gas from chemical vapor deposition (CVD), doping (diffusion and ion implantation), photolithography and cleaning, the combusted and washed discharged gas of the off-gas in other procedures after field treatment and centralized treatment, or the hydrogenous waste gas entering the hydrogen discharge system are purified to meet the standard for the electronic grade hydrogen required for the manufacturing process of semiconductor, the recycling of hydrogen resources is realized, and the yield of hydrogen is greater than or equal to 70-85%. The present invention solves the technical difficulty the normal-pressure waste hydrogen recovered in the manufacturing process of semiconductor can't be returned to the manufacturing process of semiconductor for reuse.

A method for generating Renewable Natural Gas (RNG) from raw biogas is disclosed, in which carbon dioxide is removed from biogas to generate pipeline specification RNG by a combination of absorption and membrane processes. The absorption process provides for the initial bulk carbon dioxide removal. The membrane process provides for the simultaneous removal of carbon dioxide and water vapors to pipeline specification. The method is characterized by a reduced separation energy consumption as compared to stand-alone membrane and absorption unit separations for biogas upgrading.

Adsorbent materials are disclosed, along with filter elements containing the adsorbent materials methods of using adsorbents to remove siloxane contaminants from a gas stream. The method includes providing an adsorbent material that has been washed with an acid and passing a gas through the adsorbent material so as to reduce siloxane levels in the gas. A filter element for reducing siloxane levels in a gas includes a first adsorbent material, the first adsorbent material comprising an acid-washed adsorbent; and a second adsorbent material, the second adsorbent material comprising an acid-impregnated adsorbent.

A plasma abatement process for abating effluent containing compounds from a processing chamber is described. A plasma abatement process takes gaseous foreline effluent from a processing chamber, such as a deposition chamber, and reacts the effluent within a plasma chamber placed in the foreline path. The plasma dissociates the compounds within the effluent, converting the effluent into more benign compounds. Abating reagents may assist in the abating of the compounds. The abatement process may be a volatizing or a condensing abatement process. Representative volatilizing abating reagents include, for example, CH.sub.4, H.sub.2O, H.sub.2, NF.sub.3, SF.sub.6, F.sub.2, HCl, HF, Cl.sub.2, and HBr. Representative condensing abating reagents include, for example, H.sub.2, H.sub.2O, O.sub.2, N.sub.2, O.sub.3, CO, CO.sub.2, NH.sub.3, N.sub.2O, CH.sub.4, and combinations thereof.

Methods, apparatuses, and systems related to electrochemical capture of Lewis acid gases from fluid mixtures are generally described. Certain embodiments are related to electrochemical methods involving selectively removing a first Lewis acid gas from a fluid mixture containing multiple types of Lewis acid gases (e.g., a first Lewis acid gas and a second Lewis acid gas). Certain embodiments are related to electrochemical systems comprising certain types of electroactive species having certain redox states in which the species is capable of binding a first Lewis acid gas but for which binding with a second Lewis acid gas is thermodynamically and/or kinetically unfavorable. The methods, apparatuses, and systems described herein may be useful in carbon capture and pollution mitigation applications.

A regenerable gas filter includes a housing having in-line an entrance and an exit, a pleated activated carbon fibre sheet or tube, with electrical conductors in the tip of each pleat and further electrical conductors being optionally attached to the ends of said sheet. The conductors are disposed substantially perpendicularly to the gas flow through the housing and the conductors on one side of the pleated sheet are connected to a single central conductor, which in turn was coupled to an electrical DC power source, which is repeated for the conductors on the other side of the pleated sheet. The sheet is stretched over and in electrical contact with the conductors and the pleated sheet or tube is provided with a sealing means to the housing. The regenerable gas filter is used for the purification of air in a Heating, Ventilation and Air Conditioning (HVAC) system.

A gas purifying filter includes a first gas permeable body having a gas inlet surface; a first adsorption layer disposed on the first gas permeable body and including activated carbon on which a phosphoric acid-based compound satisfying the following Formula 1 is supported; a second adsorption layer disposed on the first adsorption layer and including a hydrophobic zeolite having a SiO.sub.2/Al.sub.2O.sub.3 value of about 50 or more; and a second gas permeable body disposed on the second adsorption layer and having a gas outlet surface,

##STR00001##

where n is an integer greater than or equal to 1.

Adsorbent materials are disclosed, along with filter elements containing the adsorbent materials methods of using adsorbents to remove siloxane contaminants from a gas stream. The method includes providing an adsorbent material that has been washed with an acid and passing a gas through the adsorbent material so as to reduce siloxane levels in the gas. A filter element for reducing siloxane levels in a gas includes a first adsorbent material, the first adsorbent material comprising an acid-washed adsorbent; and a second adsorbent material, the second adsorbent material comprising an acid-impregnated adsorbent.

An aircraft pressurized air system and method is disclosed. The system includes a compressor that receives and compresses outside air, and an air cycle machine that receives compressed air from the compressor and directs conditioned air to an aircraft pressurized zone. The system also includes a contaminant sensor disposed along an air flow path between the compressor and the aircraft pressurized zone, comprising an optical guide, a metal organic framework on an exterior surface of the optical guide in operative fluid communication with air from the air flow path, a light source in communication with the optical guide at a first end of the optical guide, and a light detector in communication with the optical guide at a second end of the optical guide.

A system for processing biogas, the system comprising: a container, a pressure swing adsorption (PSA) unit housed in the container, the PSA unit having: a plurality of beds containing adsorbent material, the adsorbent material configured to selectively adsorb gas species from the biogas to process the biogas, a rotary valve module for distributing flow of 5 the biogas within the PSA unit, an inlet for supplying the biogas to the plurality of beds from outside of the container, and an outlet for transporting the processed biogas away from the PSA unit.