Indoor and outdoor air purifier including:—a fan for suctioning air and conveying it into—an air treatment duct suitable to disintegrate the toxic and pollutant components present in the air and then reintroducing the air, purified by now, into the external environment through one of the grids; within the duct, at least the following being installed: ∘ filters in any alveolar ceramic alloy treated with a titanium dioxide TiO.sub.2 nano-coating suitable to disintegrate the pollutant substances by a photocatalytic process activated thanks to ∘ LED lights, each of which installed in proximity to a corresponding filter, suitable to start the pollutant molecules disintegration photocatalytic process, reintroducing only the harmless substances into the atmosphere.

The invention generally relates to a process for purifying a hydrogen gas for use in a fuel cell. The process involves taking a hydrogen feed stream from a high-pressure tank and passing it through a purifier comprising an adsorbent to provide a purified hydrogen stream which is sent to a fuel cell. A particular adsorbent which can be used is a metal-organic framework composition. The adsorbent can be housed in a device such as a canister or cartridge having an inlet and outlet port.

A continuous desulfurization process and process system are described for removal of reduced sulfur species at gas stream concentrations in a range of from about 5 to about 5000 ppmv, using fixed beds containing regenerable sorbents, and for regeneration of such regenerable sorbents. The desulfurization removes the reduced sulfur species of hydrogen sulfide, carbonyl sulfide, carbon disulfide, and/or thiols and disulfides with four or less carbon atoms, to ppbv concentrations. In specific disclosed implementations, regenerable metal oxide-based sorbents are integrated along with a functional and effective process to control the regeneration reaction and process while maintaining a stable dynamic sulfur capacity. A membrane-based process and system is described for producing regeneration and purge gas for the desulfurization.

A polyether compound having a cationic group and two or more chain end groups and, wherein all of the chain end groups are any of a hydroxyl group and an azide group is provided.

Disclosed herein are catalyst devices for removing formaldehyde, volatile organic compounds, and other pollutants from an air flow stream, A catalyst device includes a housing, a solid substrate disposed within the housing, and a catalyst layer disposed on the substrate. The catalyst layer includes a base metal catalyst at a first mass percent and a rare earth metal catalyst at a second mass percent.

A chemical substance concentrator is configured to concentrate a chemical substance contained in a gaseous sample. The concentrator includes a flow passage having a hollow part allowing the gaseous sample flows through the hollow part, first and second electrodes disposed on an inner wall of the flow passage, an electrode wiring connected to the first and second electrodes, a material layer disposed on the electrode wiring, and an adsorbent disposed on the material layer. The adsorbent is configured to adsorb the chemical substance and to desorb the adsorbed chemical substance. The chemical substance concentrator is capable of efficiently desorbing the adsorbed chemical substances.

Disclosed herein are catalyst compositions for removing formaldehyde, volatile organic compounds, and other pollutants from an air flow stream. In one embodiment, a catalyst composition comprises manganese oxide particles and rare earth metal catalyst particles.

A system and method for processing unconditioned syngas first removes solids and semi-volatile organic compounds (SVOC), then removes volatile organic compounds (VOC), and then removes at least one sulfur containing compound from the syngas. Additional processing may be performed depending on such factors as the source of syngas being processed, the products, byproducts and intermediate products desired to be formed, captured or recycled and environmental considerations.

The invention relates to a process and a plant for removing thiols from synthesis gas. Thiols and optionally thiophene and carbon disulfide are absorbed in a dedicated absorption stage with methanol as physical absorption medium. Methanol laden with at least thiols is freed of thiols in a stripping stage with methanol vapours as stripping gas and the methanol vapours-containing thiols are freed of methanol in a scrubbing stage. The process according to the invention minimizes methanol losses and the amounts of coolant required for the process.

Disclosed in certain embodiments are methods of removing water from a gas feed stream comprising hydrocarbons and water during an adsorption step of an adsorption cycle.