An adsorbent bed, including at least one elementary composite structure that includes adsorbent particles in a polymer matrix, wherein the adsorbent bed has a bed packing, ρ.sub.bed, defined as a volume occupied by the at least one elementary composite structure V.sub.ecs divided by a volume of the adsorbent bed V.sub.bed where ρ.sub.bed is greater than 0.60.

An oxygen concentrator 100 apparatus and a method thereof implement operations control to efficiently release oxygen enriched gas to reduce potential waste. The control methodology may include generating a profile such as a minimum inhalation flow profile of the user. The profile may be based on a size parameter of the user. The method may determine one or more control parameters characterizing a bolus of oxygen enriched gas based on the generated flow profile. The control methodology may then generate a bolus release control signal, such as for a supply valve, according to the determined one or more control parameters. The oxygen concentrator may then, with the control signal, release and deliver a bolus of oxygen enriched gas for a user such as for reducing waste.

An absorption tower for production of nitric acid by the Ostwald process may include sieve trays that are arranged on top of one another and each spaced apart from one another, a water inlet in an upper region of the absorption tower, an inlet for gaseous nitrogen oxides in a lower region of the absorption tower, and a column bottom that is disposed in the lower region of the absorption tower beneath a lowermost sieve tray and is divided by a dividing wall into a first, radially inner region and at least a second, radially outer region. Nitric acid that trickles down from the lowermost sieve tray with a higher concentration can be collected in a middle region. The less-concentrated nitric acid that then effluxes from sieve trays higher up can then be collected separately in a region farther outward.

The present invention relates to an adsorption process for xenon recovery from a cryogenic liquid or gas stream wherein a bed of adsorbent is contacted with a xenon-containing liquid or gas stream selectively adsorbing the xenon from said stream. The adsorption bed is operated to at least near full breakthrough with xenon to enable a deep rejection of other stream components, prior to regeneration using the temperature swing method. After the stripping step, the xenon adsorbent bed is drained to clear out the liquid residue left in the nonselective void space and the xenon molecules in those void spaces is recycled upstream to the ASU distillation column for increasing xenon recovery. The xenon adsorbent bed is optionally purged with oxygen, followed by purging with gaseous argon at cryogenic temperature (≤160 K) to displace the oxygen co-adsorbed on the AgX adsorbent due to higher selectivity of argon over oxygen on the AgX adsorbent. By the end of this step, the xenon adsorbent bed is filled with argon and xenon. Then the entire adsorbent bed is heated indirectly without utilizing any of the purge gas for direct heating. Operating the adsorption bed to near full breakthrough with xenon and displacing the adsorbed oxygen and other residues with argon, prior to regeneration, along with indirect heating of the bed, enables production of a high purity product ≥40 vol % xenon from the adsorption bed and further enables safely heating without any purge gas and ease for downstream product collection, even in cases where hydrocarbons are co-present in the feed stream.

The present invention discloses a method of separating C8 aromatic hydrocarbon isomers. The anion-pillared metal-organic framework materials with a pore diameter of 5-10 Å is used as adsorbents to achieve selective adsorption and separation of C8 aromatic hydrocarbon isomers by contacting the C8 aromatic hydrocarbon isomers with the adsorbents; the anion-pillared microporous materials are porous materials formed by metal ion M, inorganic anion A and organic ligand L through coordination bonds, with the general formula of [MAL.sub.2].sub.n, where n>4 and n is an integer; the descried “metal ion M” is Fe.sup.2+, Co.sup.2+, Ni.sup.2+, Cu.sup.2+; the descried “inorganic anion A” is SiF.sub.6.sup.2−, NbOF.sub.5.sup.2−, TaF.sub.7.sup.2−, ZrF.sub.6.sup.2−, TiF.sub.6.sup.2−, GeF.sub.6.sup.2−, SO.sub.3CF.sub.3.sup.−, NbF.sub.6.sup.−; the descried “organic ligand L” is selected from any of the following:

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A plant for purifying a gas stream comprising at least 0.02% by volume of water, CO.sub.2 and NOx, comprising an adsorber characterized by: a cavity (1); an adsorbent (2) included in the cavity (1); an outer casing (3) made of carbon steel; an inner casing (4) made of stainless steel making a space having a width of between 10 and 100 mm between said inner casing and the outer casing, said space being at equal pressure with the cavity.

An adsorber for purifying or separating a gas stream, wherein a granular-material filling system is made up of a cylinder that is perforated over all or part of its height, of the top end thereof of diameter Dext, and of the bottom end thereof. The distance Din-Dext is greater than twice the size of particles of the second granular material. A first granular material and the second granular material follow one another in the direction of circulation of the gas stream and are such that M>ADN. And, the second granular material is in contact both with at least a part of the outer surface of the granular-material filling system and at least a part of the inner surface of the domed top end.

This disclosure relates to the adsorption and separation of fluid components, such as oxygen, in a feed stream, such as air, using zeolite ITQ-55 as the adsorbent. A process is disclosed for adsorbing oxygen from a feed stream containing oxygen, nitrogen and argon. The process comprises passing the feed stream through a bed of an adsorbent comprising zeolite ITQ-55 to adsorb oxygen from the feed stream, carrying out an equalization step to improve recovery, thereby producing a nitrogen product stream depleted in oxygen as well as a waste stream can be collected to have enriched oxygen. The kinetic selectivity and related mass transfer rates can be tuned by varying the mean crystal particle size of zeolite ITQ-55 within the range of from about 0.1 microns to about 40 microns, or by varying the adsorption temperature within the range from about -195° C. to about 30° C., or by varying the adsorption pressure within the range from about 1 bar (~14.7 psi) to about 30 bar (~435 psi), or combinations thereof. The feed stream is exposed to the zeolite ITQ-55 at effective conditions for performing a rapid cycle of kinetic separation, in which oxygen exhibits greater kinetic selectivity than nitrogen and argon.

A method for removing sulfur-based gases from a gas stream comprises contacting a sulfur containing gas stream under dynamic flow conditions with granular activated carbon (GAC) to adsorb substantially all sulfur-containing gas from the gas stream. The granular activated carbon (GAC) can be derived from date palm pits.

Some implementations can include a desiccant breather having an inner pipe having a top portion with a lip extending radially from the inner pipe, the inner pipe having a threaded portion and a top connector. The desiccant breather can also include an outer pipe having a diameter sufficient to accommodate the inner pipe, the outer pipe having a bottom connector and a cap. The desiccant breather can further include a desiccant breather body portion having a cavity configured to hold desiccant material. The lip of the inner pipe can have a diameter equal to or greater than a diameter of the outer pipe.