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 portable oxygen concentrator designed for medical use where the sieve beds, adsorbers, are designed to be replaced by a patient. The concentrator is designed so that the beds are at least partially exposed to the outside of the system and can be easily released by a simple user-friendly mechanism. Replacement beds may be installed easily by patients, and all gas seals will function properly after installation.

A cartridge comprising layers of adsorbent sheet is described. The cartridge includes an indicator that characterizes the consumption state of the adsorbent within the cartridge. The indicator is applied in a way such that discrete areas of indicator are visible. These discontinuous areas of indicator may be applied to the outside surface of the cartridge. Alternatively, the discontinuous areas may be formed by cutting windows in the outermost layer of the cartridge and either coating indicator on the layer beneath the window, placing an indicator layer between the window and the layer beneath it or filling the window with an indicating plug of material so that the indicator is visible from the outside of the cartridge. The indicator layer and indicator plug embodiments allow the use of any indicator with any adsorbent.

Provided is an oxygen concentration device that can facilitate easy and secure replacement work, such as attaching and detaching the adsorption cylinder while reducing the force applied from the oxygen concentration device body to the adsorption cylinder cartridge in the direction of detaching and thus ensuring the connection with the oxygen concentration device, wherein the axis line of the gas flow direction of the adsorption cylinder intersects with either connection axis in the end part for supplying pressurized air to the adsorption cylinder or the end part for extracting oxygen from the adsorption cylinder.

A diagnostic device is configured to execute a first acquisition process of acquiring a remaining amount of evaporated fuel in a fuel tank when an ignition switch turns off, as an end remaining amount, a determination process of, after the first acquisition process, determining whether there is a blockage of a vapor passage by reducing a pressure in a vapor passage with a pressure reducing pump when the end remaining amount is smaller than a prescribed value while the ignition switch is off, a second acquisition process of, after the determination process, acquiring a remaining amount of liquid fuel in the fuel tank when the ignition switch turns on, as a start remaining amount, and an invalidation process of invalidating a determination result that a blockage is present in the vapor passage in the determination process when the start remaining amount is larger than or equal to a set value.

An adsorption device for compressed gas, is provided with a vessel with an inlet for the supply of a compressed gas to be treated, and an outlet for treated gas and an adsorption element is affixed in the vessel. The adsorption element extends along the flow direction of the compressed gas to be treated, between the inlet and the outlet. The adsorption element has a monolithic supporting structure that is at least partially provided with a coating that contains an adsorbent.

Embodiments of the invention include a filtration element. In an embodiment, the invention includes a filtration element for an airplane cabin that includes a first media portion upstream from a second media portion. The first media portion can include activated carbon. The second media portion can include a catalyst material. Other embodiments are also included herein.

An indicator is provided in a vehicle for indicating necessity of change of a fuel vapor absorber in a venting line of a vehicle tank, especially a methanol tank for fuel cell vehicles.

A compressor assembly for a portable oxygen concentrator includes a first compressor chamber having a first connector, a second compressor chamber having a second connector, and a tube having a first end having a first connection interface configured to connect to the first connector and a second end having a second connection interface configured to connect to the second connector. The first connection interface is shaped to maintain the connection between the first connector and the first connection interface in a fixed orientation and the second connection interface is shaped to maintain the connection between the second connector and the second connection interface in a fixed orientation. One or more of the first connector, the second connector, and the tube are compliant.

An adsorbent composition for capturing pollutants includes a porous composition that includes a plurality of ferric oxyhydroxide particles and an additional component in the porous composition. The additional component includes one of copper chloride (CuCl.sub.2), zinc chloride (ZnCl.sub.2), polyvinylpolypyrrolidone, silicon carbide, silicon dioxide, activated carbon or other carbonaceous material, and a combination thereof.