Disclosed are processes for removing H.sub.2S from gas streams containing H.sub.2S, the processes comprise contacting gas streams with a mixed metal oxy-hydroxide media comprising two or more metals selected from the group consisting of magnesium, chromium, manganese, iron, cobalt, zinc and copper. Also disclosed are processes for removing H.sub.2S from gas streams containing H.sub.2S, the processes comprise contacting the gas streams with a mixed metal oxy-hydroxide media comprising one or more metals selected from the group listed above plus one or more metals selected from the group consisting of aluminum, silicon, titanium and zirconium.

Disclosed are a carbon dioxide absorbent composition in which an N-alkylaminoalkanol; a polyhydroxyamine-based compound; and ethylenediamine and/or diethylenetriamine are mixed, a method for preparing the same, and a method and an apparatus for carbon dioxide absorption/separation using the same. Since the carbon dioxide absorbent according to the present disclosure has superior carbon dioxide absorption capacity and remarkably lower absorbent recycling temperature as compared to the existing absorbents such as monoethanolamine, etc., total energy consumption in the capturing process can be reduced greatly. In addition, since carbon dioxide is recovered at low recycling temperature, contamination by water or absorbent vapor may be prevented.

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.

A separation and purification coupled process with a high helium yield and diversified products is provided The process is as follows. Firstly, a low-concentration helium-containing gas after being pressurized and pre-treated enters a two-stage and two-section membrane separation unit to produce a helium product with a medium concentration by concentrating stage by stage through the membrane separation unit. A part of the helium with medium concentration enters an adsorption unit for further concentration to produce a helium product above grade A.

Disclosed is an adsorbent containing a metal oxide for adsorption of hydrogen sulfide in biogas, and a biogas purification system using the same.

A facility and method for membrane permeation treatment of a feed gas flow containing at least methane and carbon dioxide that includes a compressor, a gas analyser, at least one valve, and first, second, third, and fourth membrane separation units for separation of CO.sub.2 from CH.sub.4 to permeates enriched in CO.sub.2 and retentates enriched in CH.sub.4, respectively. A pressure of the feed gas flow is adjusted according to a CH.sub.4 concentration of the second retentate.

Embodiments relate to a gas dehydration drying agent solution composition, comprising a solvent that includes at least one glycol having a number average molecular weight from 40 g/mol to 500 g/mol and from 0.01 wt % to 8.00 wt % of a cyclohexylamino sulfonic salt.

An absorption system (100) and a process for absorption of gas from a medical apparatus (1) are provided. The absorption system includes a feed line (6), a discharge line (8), a filter unit (4) with a filter and at least one buffer storage device. The feed line establishes a fluid connection between the medical apparatus and the filter unit. The discharge line establishes a fluid connection between the filter unit and a fluid absorption unit (7). The gas is discharged from the medical apparatus and is passed through the feed line to the filter unit and from there through the discharge line to the fluid absorption unit. The filter filters at least one gas component out of the gas that is passed through the filter unit. The one or more buffer storage device absorbs and again discharges gas from time to time.

A method for regenerating an amine-based, acid gas absorbent using a mixed catalyst containing silver oxide and silver carbonate includes the steps of absorbing an acid gas into an acid gas absorbent having an amine group to obtain an acid gas-absorbed absorbent; and regenerating the amine-based, acid gas absorbent by adding a catalyst mixture containing silver oxide and silver carbonate to the acid gas-absorbed absorbent and by removing the acid gas at a temperature ranging from 40° C. to 86° C. When the amine-based acid gas absorbent is an acid gas absorbent solution and when the acid gas that is absorbed into the acid gas absorbent solution is carbon dioxide, the catalyst mixture efficiently promotes decomposition of carbon dioxide-bound carbamate in the acid gas absorbent solution that absorbs the carbon dioxide through a novel catalytic reaction pathway.

This invention relates to a process and apparatus for growing agricultural products with a reduced abundance of radioactive carbon-14 (.sup.14C) by employing centrifugal separation of atmospheric gases to selectively remove carbon dioxide (CO.sub.2) with .sup.14C. Agricultural products with reduced .sup.14C content can be grown in controlled environments with filtered atmospheric gases for the benefit of reducing harmful damage to human DNA that is unavoidable with our current food chain, due to the natural abundance of .sup.14C in atmospheric gases. Bilateral and unilateral compression helikon vortex apparatus provide efficient and economical removal of CO.sub.2 with .sup.14C from atmospheric gases with a single filtration pass, which is ideally suited for large scale agricultural production.