In a process for treating a carbon dioxide-rich gas (1) containing water, the treatment by compression and/or washing and/or drying of the gas produces acidified water (W1, W2, W3, W4, W7) which is sent to a cooling circuit (W8, W10).

An embodiment ceria-alumina support (CeO.sub.2—Al.sub.2O.sub.3 support) includes a nano-ceria having a shape of a polygonal bipyramid or a truncated polygonal bipyramid supported on alumina. An embodiment noble metal catalyst for treating exhaust gas includes a noble metal deposited on a ceria-alumina support (CeO.sub.2—Al.sub.2O.sub.3 support) that includes a nano-ceria having a shape of a polygonal bipyramid or a truncated polygonal bipyramid supported on alumina. An embodiment method for affecting resistance to sulfur-poisoning of a noble metal catalyst through structural transformation of nano-ceria supported on alumina includes performing a hydrothermal treatment of ceria supported on γ-alumina.

Systems and methods for eliminating carbon dioxide and capturing solid carbon are disclosed. By eliminating carbon dioxide gas, e.g., from an effluent exhaust stream of a fossil fuel fired electric power production facility, the inventive concepts presented herein represent an environmentally-clean solution that permanently eliminates greenhouse gases while at the same time producing captured solid carbon products that are useful in various applications including advanced composite material synthesis (e.g., carbon fiber, 3D graphene) and energy storage (e.g., battery technology). Capture of solid carbon during the disclosed process for eliminating greenhouse gasses avoids the inefficiencies and risks associated with conventional carbon dioxide sequestration. Colocation of the disclosed reactor with a fossil fuel fired power production facility brings to bear an environmentally beneficial, and financially viable approach for permanently capturing vast amounts of solid carbon from carbon dioxide gas and other greenhouse gases that would otherwise be released into Earth's biosphere.

A gas separation system has system input inlet configured to receive a stream mixture including a target gas, one or more spray generators positioned to spray a non-sprayable liquid to change a concentration of the target gas in the non-sprayable liquid, one or more system outlets positioned to outlet an output material, wherein at least one of the system outlets outputs a material having a lower amount of the target gas than the input stream mixture, and a recirculating path connected to the one or more outputs and the input inlet to allow recirculation of the non-sprayable liquid. A method of performing gas separation includes absorbing a target gas from an input stream in a non-sprayable capture liquid, and releasing the target gas in an output gas stream by spraying the non-sprayable capture liquid into a heated volume using a spray generator. A method of performing gas separation includes receiving an input stream that includes a target gas, using one or more spray generators to apply a non-sprayable liquid as a spray to the input stream to change a concentration of the target gas in the liquid, and outputting the liquid with the changed concentration through an outlet.

An apparatus for the gas treatment including a reaction chamber. The reaction chamber including an inlet opening of a flow of gas to be treated; means for the formation of ionizing electrical discharges adapted to interact with the gas to be treated to form a plasma state for obtaining a flow of treated gas which includes at least a high-added value fraction and at least a waste fraction; an outlet opening of the high-added value fraction arranged downstream of the means for the formation with respect to the direction of forward movement of the flow of gas to be treated inside the reaction chamber; reintroduction means for reintroducing the waste fraction inside the reaction chamber, and the reintroduction means being arranged downstream of the means for the formation with respect to the direction of forward movement.

A method for regenerating a deNO.sub.x catalyst includes contacting the catalyst with steam at a temperature in the range of from 250 to 390° C. The method also includes reducing the amount of nitrogen oxide components in a process gas stream that includes a) contacting the process gas with a deNO.sub.x catalyst which results in the conversion of nitrogen oxide components as well as a decline in the NO.sub.x conversion over the deNO.sub.x catalyst; and b) regenerating the deNO.sub.x catalyst to improve the NO.sub.x conversion by contacting the deNO.sub.x catalyst with steam at a temperature in the range of from 250 to 390° C.

Solid sorbents, and especially zeolites, are attractive candidates for CO.sub.2 direct air capture (DAC) and point source capture applications because of their potential for high selectivity, fast kinetics, and low energy CO.sub.2 capture cycles. A common issue with solid sorbents, including zeolites, is their low thermal conductivity, which makes them difficult to heat for regeneration without using complex and expensive heat transfer systems. This invention utilizes a modified TVSA process which utilizes the product CO.sub.2 gas itself as the heating medium for the adsorbent bed, alone or in conjunction with internal or external heaters. The use of CO.sub.2 as a heating medium allows efficient heating of the sorbent bed and enables high purity CO.sub.2 product.

A high selectivity and high CO.sub.2 plasticization resistant polymer comprises a plurality of repeating units of formula (I) for gas separation applications. The polymer may be synthesized from a superacid catalyzed poly(hydroalkylation) reaction.

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Membranes made from the polymer and gas separation processes using the membranes made from the polymer are also described.

Disclosed herein are aluminum oxide aerogels and methods of making and use thereof. The methods of making the aluminum oxide aerogel include contacting a solid comprising aluminum with a Ga-based liquid alloy to dissolve at least a portion of the aluminum from the solid, thereby forming an aluminum-alloy mixture; and contacting the aluminum-alloy mixture with a fluid comprising water, thereby forming the aluminum oxide aerogel. In some examples, the methods can further comprise capturing and converting carbon dioxide to a syngas comprising carbon monoxide and hydrogen.

A process for recovering nitric acid or salts thereof, comprising: contacting, in the presence of water, an water-immiscible ionic liquid of the formula [A.sup.+][X.sup.−], wherein [A.sup.+] represents a phosphonium or ammonium cation and [X.sup.−] represents a counter anion which is NO.sub.3.sup.−, an halide anion displaceable by NO.sub.3.sup.−, or both, with a fluid which contains HNO.sub.3 and at least one more mineral acid, or precursors of said acids, and partition, under mixing, said acids between aqueous and organic phases and form nitrate-loaded ionic liquid of the formula [A.sup.+][NO.sub.3.sup.−].sub.z>0.25 where Z indicates a molar amount of nitrate held in the ionic liquid beyond the positions occupied by the nitrate counter ions; separating the so-formed mixture into an organic phase comprising a nitrate-loaded ionic liquid of the formula [A.sup.+][NO.sub.3.sup.−].sub.z>0.25 and an aqueous phase consisting of a nitrate-depleted aqueous solution that contains the other mineral acid(s); stripping the nitric acid from said nitrate-loaded ionic liquid to create an aqueous nitrate solution and regenerate ionic liquid of the formula [A.sup.+][NO.sub.3.sup.−].sub.z≥0 with reduced nitrate loading, or unloaded [A.sup.+][NO.sub.3.sup.−].sub.z=0 ionic liquid.