A method including capturing carbon dioxide (CO.sub.2) from air (e.g., atmosphere) in an absorber in which the air contacts a base (e.g., a hydroxide, such as potassium hydroxide KOH and/or sodium hydroxide (NaOH)) to produce a carbonate (e.g., potassium carbonate (K.sub.2CO.sub.3) and/or sodium carbonate (Na.sub.2CO.sub.3)); precipitating one or more (e.g., carbonate) salt from an aqueous solution comprising salt (a brine) to provide an aqueous solution comprising a chloride (e.g., potassium chloride (KCl) and/or sodium chloride (NaCl)); using electrochemical regeneration to convert the chloride to electrochemically regenerated product comprising the base (e.g., KOH and/or NaOH); and recycling at least a portion of the electrochemically regenerated product comprising the base to the capturing of the CO.sub.2 from the air. A system for carrying out the method is also provided.

This disclosure provides a halogenated activated carbon composition comprising carbon, a halogenated compound and a salt. In some embodiments, the halogenated compound and the salt comprise a naturally occurring salt mixture, as may be obtained from ocean water, salt lake water, rock salt, salt brine wells, for example. In some embodiments, the naturally occurring salt mixture comprises Dead Sea salt.

This disclosure provides a halogenated activated carbon composition comprising carbon, a halogenated compound and a salt. In some embodiments, the halogenated compound and the salt comprise a naturally occurring salt mixture, as may be obtained from ocean water, salt lake water, rock salt, salt brine wells, for example. In some embodiments, the naturally occurring salt mixture comprises Dead Sea salt.

A gas purification apparatus includes: a housing to which a gas is introduced; a filter portion for removing an impure substance in the gas from the gas, the filter portion being disposed inside the housing; and a gas purification agent for removing a removal target substance in the gas from the gas, the gas purification agent being disposed, inside the housing, on the filter portion or in a space at a downstream side of the filter portion with respect to a flow of the gas.

A pressure swing adsorption process is provided to remove oxygen from a hydrogen stream through the use of a copper material in combination with layers of adsorbent to remove water, C2 and C3 hydrocarbons, as well as other impurities. The feed gas comprises more than 70 mol % hydrogen, at least 1 mol % methane and more than 10 ppmv oxygen. The purified product hydrogen stream comprises greater than 99 mol % hydrogen, with less than 1 ppmv oxygen.

A system includes a catalyst for receiving and treating exhaust gas generated by an engine, a passive NOx adsorber (PNA) positioned upstream of the catalyst, a bypass valve positioned upstream of the catalyst and the PNA, and a controller. The controller is configured to, determine that the catalyst is operating under cold start conditions, control the bypass valve to direct exhaust gas to the PNA, determine that the catalyst is no longer operating under cold start conditions and continue to control the bypass valve to direct exhaust gas to the PNA for a predetermined duration, and after the elapse of the predetermined duration, control the bypass valve to direct exhaust gas to the catalyst bypassing the PNA. The controller is also configured to detect a high transient torque demand while the exhaust gas is provided to the PNA, and split the torque demand between the engine and an electric motor.

According to one embodiment, a gas processing equipment includes an oxygen remover 2 that removes oxygen contained in exhaust gas G, and a gas processing device 3 that processes pretreated exhaust gas G (P), from which the oxygen has been removed by the oxygen remover 2, with a carbon dioxide absorbent solvent S as a treatment agent.

Purified air is provided, having a TVOC content of from less than 5 ppb to about 500 ppb, a Biologicals content of from less than 1 CFU/M.sup.3 to 150 CFU/M.sup.3 and a Particulate content of from about 1,000 0.3 μm particles per ft.sup.3 to about 50,000 0.3 μm particles per ft.sup.3, or from about 600 0.5 μm particles per ft.sup.3 to about 500,000 0.5 μm particles per ft.sup.3.

A multi-functional composition of matter that is useful for injection into a flue gas stream to rapidly and efficiently remove mercury from the flue gas streams, particularly at above average flue stream temperatures of about 340° F. or higher. The multi-functional composition of matter may include a fixed carbon content of at least about 20 wt. %, a mineral content of from about 20 wt. % to about 50 wt. %, a sum of micropore plus mesopore volume of at least about 0.20 cc/g, a micropore volume to mesopore volume ratio of at least about 0.7, and a tapped density of not greater than about 0.575 g/ml. These compositions may be further characterized by number of particles per gram of the composition of matter such that the composition may have at least about 0.8 billion particles per gram, or even as many as 1.5 billion particles per gram. These physical and chemical properties may enhance (1) the oxidation reaction kinetics for the oxidation of mercury species, (2) frequency of contact events, and (3) capture and sequestration of mercury, to achieve efficient mercury capture by the composition even in high temperature flue gas streams.

This disclosure provides a halogenated activated carbon composition comprising carbon, a halogenated compound and a salt. In some embodiments, the halogenated compound and the salt comprise a naturally occurring salt mixture, as may be obtained from ocean water, salt lake water, rock salt, salt brine wells, for example. In some embodiments, the naturally occurring salt mixture comprises Dead Sea salt.