Geomass mediated carbon dioxide (CO.sub.2) sequestering methods and systems are provided. Aspects of the methods include contacting a gaseous source of CO.sub.2 and an aqueous capture ammonia to produce a CO.sub.2 sequestering product and an aqueous ammonium salt, and then contacting the aqueous ammonium salt liquid with a geomass, e.g., alkaline waste product, to regenerate the aqueous capture ammonia. Also provided are systems configured for carrying out the methods.

The present application pertains to methods for making metal oxides and/or citric acid. In one embodiment, the application pertains to a process for producing calcium oxide, magnesium oxide, or both from a material comprising calcium and magnesium. The process may include reacting a material comprising calcium carbonate and magnesium carbonate. Separating, concentrating, and calcining may lead to the production of oxides such as calcium oxide or magnesium oxide. In other embodiments the application pertains to methods for producing an alkaline-earth oxide and a carboxylic acid from an alkaline earth cation—carboxylic acid anion salt. Such processes may include, for example, reacting an alkaline-earth cation—carboxylic acid anion salt with aqueous sulfur dioxide to produce aqueous alkaline-earth—bisulfite and aqueous carboxylic acid solution. Other useful steps may include desorbing, separating, and/or calcining.

Devices, systems and methods for capturing CO.sub.2 in a form that can be stored, processed, and/or converted to usable products is desirable. Systems capture CO.sub.2 using small scale, individual devices at a vast number of locations which, in the aggregate, are capable of significantly decreasing CO.sub.2 concentrations in the atmosphere on a global scale. When such small devices are placed in areas already occupied with a structure, i.e., office buildings, apartments, homes, automobiles and the like, though the amount of CO.sub.2 removal by each individual device may be relatively small, in the aggregate, significant amounts of CO.sub.2 may be removed at a more macro or even global scale.

Carbon dioxide removal using lithium borate is generally described.

Nitrogen oxides formed in combustion engines are recycled such that the nitrogen oxides can be utilized for producing liquid or solid chemicals. The nitrogen oxides are recycled by a method including an adsorber material adsorbing nitrogen oxides from an exhaust-gas stream of the combustion engine, removing the adsorber material laden with nitrogen oxides, desorbing the adsorbed nitrogen oxides from the adsorber material, and converting the nitrogen oxides desorbed from the adsorber material into liquid or solid nitrogen-containing compounds.

A system and method for providing inerting gas to a protected space is disclosed. The system includes an air separation module that includes an air inlet, a membrane with a permeability differential between oxygen and nitrogen, a nitrogen-enriched air outlet, and an oxygen-enriched air outlet. The system also includes an air flow path between an air source and the air separation module inlet, and an inerting gas flow path between the air separation module nitrogen-enriched air outlet and the protected space.

Provided are sorbents and associated methods and systems for removing mercury from process gases or fluid streams. The sorbents may include activated carbon and pyrite. The sorbents may optionally include one or more additives, such as a halide salt.

The present disclosure relates to systems and methods of making ammonia using stable ammonia absorbents. The system and method for producing ammonia, comprises a reactor comprising a catalyst that converts at least a portion of nitrogen feed gas and at least a portion of hydrogen feed gas to ammonia (NH3) forming a reaction mixture comprising the ammonia, unreacted nitrogen, and unreacted hydrogen. An absorber configured to selectively absorb ammonia from the reaction mixture at a temperature of about 180 deg. C. to 330 deg. C. and a pressure of about 1-20 bar, the absorber comprising a solid absorbent. Preferably the solid absorbent is at least one metal halide and a solid support. The unabsorbed ammonium, the unreacted nitrogen, and unreacted hydrogen gas are recycled to the reactor.

Gas separation modules and methods for use including an integrated adsorbent and membrane. In certain refining applications, it is paramount to obtain high purity product gases. Adsorbent beds are effective at removing certain contaminants, such as CO.sub.2, from gas streams containing product and contaminant constituents to form a product-rich stream. The integrated membrane permits a further separation of products from any unadsorbed contaminant to produce a high purity product, such as hydrogen, stream. The gas separation modules described herein include stacked, radial, and spiral arrangements. Each modules includes a configuration of feed and cross-flow channels for the collection of contaminant gases and/or high purity product gases.

A process is disclosed for reversibly absorbing carbon dioxide to an alkali metal or earth alkaline absorbent. For absorption the absorbent is contacted with a first gas composition. For desorption the absorbent is contacted with a second gas composition. The moisture contents of the first and second gas compositions are controlled so that during the absorption step the absorbent is converted to a bicarbonate, and during the desorption step the absorbent is converted to a carbonate hydrate. Compared to prior art processes the process of the invention requires less energy input. The process of the invention is particularly suitable for producing a carbon dioxide enriched gas for accelerating plant growth in a greenhouse.