The present invention comprises a one-stage membrane process for electrochemical separation of hydrogen from natural gas streams in a pipeline (1) having a positive pressure in the range from 50 mbar to 100 bar, having the following process steps: (i) a gas substream (2) is drawn off from the natural gas stream in a pipeline (1) without any change in the gas composition, where the mass flow rate of the gas substream is adjusted depending on the hydrogen content in the natural gas stream (1) such that a depletion level of 0.65 to 0.975 is established in the case of a hydrogen concentration of <10% by volume and a depletion level of 0.55 to 0.925 in the case of a hydrogen concentration of >10% by weight, where the depletion level is defined as the quotient of the desired molar H2 product stream (6) and the molar H2 reactant flow rate in the gas substream at the inlet of the membrane unit (2), (ii) this gas substream (2) is compressed (3) upstream of a membrane unit (5), (iii) this gas substream is heated to 100 to 250° C. either upstream of the membrane unit or in the membrane unit, and this gas substream is supplied with water (4) upstream of the membrane unit and/or on the permeate side of the membrane unit (4a), such that the water loading is between 0.005 and 0.2 mol of water/mol of natural gas, (iv) this gas substream is sent to an electrochemical membrane unit in which hydrogen is separated off as permeate (6a) at a temperature of 100 to 250° C., (v) the retentate (8) from the membrane unit is recycled into the natural gas stream, sent to a chemical utilization and/or used as fuel.

The present invention further comprises a method of ascertaining the optimized gas substream which is drawn off from a pipeline that conducts natural gas and hydrogen in order to separate hydrogen from this gas substream in an electrochemical membrane unit.

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.

A method for recovering helium from a feed gas mixture comprising helium, carbon dioxide and at least one of methane and nitrogen, and wherein at least a part of the feed gas mixture is subjected to a separation sequence including a membrane-based separation and an adsorption-based separation forming a helium product, wherein the the membrane based separation is performed using a first membrane separation step and a second membrane separation step, the membrane based separation and the separation sequence includes no further membrane separation steps, the adsorption based separation is performed using a pressure swing adsorption step, at least a part of the feed gas mixture is subjected to the first membrane separation step forming a first retentate and a first permeate. A corresponding arrangement is also provided.

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.

A waste water treatment system for removing contaminant chemicals, bacteria and organic matter to reduce the chemical oxygen demand (COD) and the biological oxygen demand (BOD). The system uses thermal energy to remove chemicals that can be oxidized to reduce the COD, and to destroy bacteria and organic matter to reduce the BOD of the treated water. The system can include an expansion chamber and a nozzle to create steam which can be used as thermal energy to heat the waste water and provide the proper treatment to reduce the COD and BOD of the processed waste water.

The present invention relates to novel sulfur-doped carbonaceous porous materials. The present invention also relates to processes for the preparation of these materials and to the use of these materials in applications such as gas adsorption, mercury and gold capture, gas storage and as catalysts or catalyst supports.

A method for separating N.sub.2 from a hydrocarbon gas mixture containing N.sub.2 comprising the steps of: i) providing a bed of adsorbent selective for N.sub.2; (ii) passing the hydrocarbon gas mixture through the bed of adsorbent to at least partially remove N.sub.2 from the gas mixture to produce: (a) N.sub.2-loaded adsorbent and (b) N.sub.2-depleted hydrocarbon gas mixture; iii) recovering the N.sub.2-depleted hydrocarbon gas mixture; iv) regenerating the N.sub.2-loaded adsorbent by at least partially removing N.sub.2 from the adsorbent; and v) sequentially repeating steps (ii) and (iii) using regenerated adsorbent from step (iv); wherein the adsorbent comprises a pyrolized sulfonated macroporous ion exchange resin.

A process for the purification of CO.sub.2 from chlorinated hydrocarbons and non-chlorinated hydrocarbons, comprising: contacting a CO.sub.2 stream with a chromium oxide catalyst, wherein the stream comprises the CO.sub.2, and impurities, wherein the impurities comprise the non-chlorinated hydrocarbons and the chlorinated hydrocarbons; forming a purified CO.sub.2 stream by interacting the impurities with the chromium oxide catalyst to form additional CO.sub.2 and chromium chloride; and regenerating the chromium oxide catalyst by contacting the chromium chloride with an oxygen containing gas stream.

Provided are a methane-selective composite membrane comprising: a UiO-66 type organic-inorganic composite nanoporous material, a MIL-100 type organic-inorganic composite nanoporous material, or a ZIF-8 type organic-inorganic composite nanoporous material to which a methane-selective functional group is introduced for selectively separating methane from a gas mixture containing methane/nitrogen, a use thereof, and a method of preparing the same.

A system including biogas purification and provides biogas as feedstock to a solid oxide fuel cell. The biogas purification treatment process provides a polished biogas that is substantially free of carbonyl sulfides and hydrogen sulfide. The system uses a biogas treatment apparatus, that includes apparatus such as a packed columns, comprising copper oxide or potassium permanganate packing material, and an activated carbon component configured to treat the biogas by polishing it to remove carbonyl sulfides and deleterious trace residues, such as hydrogen sulfide, that were not removed by any prior bulk H2S removal steps. In addition, an oil removal device is used to remove any entrained fine oil droplets in the biogas. A polished biogas having in the range of 60% methane is charged to the fuel cell. Electricity generated may be fed into a grid or used directly as energy to charge electrical-powered vehicles, for example. Energy credits are tracked in real time and are appropriately assigned.