The use of the combination of (a) an amino compound and (b) a compound including a soft electrophilic centre to scavenge and retain acidic sulfide species at a higher temperature and/or scavenge acidic sulfide species at an increased rate compared to that achieved using the amino compound alone.

An absorbent composition including an amino-siloxane is presented. The amino-siloxane includes structure (I): wherein R.sup.1 is independently at each occurrence a C.sub.1-C.sub.6 aliphatic or aromatic radical; R.sup.2 is independently at each occurrence a C.sub.2-C.sub.10 aliphatic or aromatic radical; and R.sup.3 is independently at each occurrence a C.sub.1-C.sub.18 aliphatic or aromatic radical or R.sup.4′ wherein R.sup.4 comprises structure (II): wherein X is independently at each occurrence an electron donating group; and n is at least 1. Methods of reducing an amount of carbon dioxide in a process stream using the absorbent composition are also presented.

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The combined acid gas removal and water filtration system (10) removes sour gases, such as hydrogen sulfide (H2S) and carbon dioxide (CO2), from an input gaseous hydrocarbon stream (FG), as well as producing purified water (TW). The acid gas removal system (10) has a contactor (12) for contacting the input gaseous stream (FG) with an absorption liquid solvent (ALS), and a stripper (24) for recycling the absorption liquid solvent (ALS) and removing acidic gases (AG) therefrom. A first heat exchanger (22) heats used absorption liquid solvent (UALS) output from the contactor (12) prior to injection into the stripper (24). A second heat exchanger (26) cools recycled absorption liquid solvent (RALS) using a refrigerant (R) before injection back into the contactor (12). The refrigerant (R) is coupled with an absorber (84), which receives a dilute ethanolic draw solution (DDS) from a forward osmosis filtration system (72), producing purified water (TW).

A carbon dioxide reduction system includes: an absorption tower configured to bring a source gas containing carbon dioxide into contact with an absorption liquid composed of an aqueous solution containing at least one amine compound so that the carbon dioxide is absorbed in the absorption liquid; an electrolysis apparatus for electrolyzing the carbon dioxide absorbed in the absorption liquid in the absorption tower; and a circulation line for circulating the absorption liquid between the absorption tower and the electrolysis apparatus.

Methods and systems are provided for a multiplexed phase separating inertial filter that is composed of helical through holes generating centrifugal separating forces. In one example, the inertial filter may be a planar porous material with an array of helical channels, each helical channel of the array of helical channels extending from a top surface of the porous material to a bottom surface of the porous material.

Methods for enzyme-enhanced CO.sub.2 capture include contacting a CO.sub.2-containing gas with an aqueous absorption solution at process conditionssuch as high temperature, high pH, and/or using carbonate-based solutionsin the presence of Thermovibrio ammonificans carbonic anhydrase (TACA) or functional derivative thereof for catalyzing the hydration reaction of CO.sub.2 into bicarbonate and hydrogen ions and/or catalyzing the desorption reaction to produce a CO.sub.2 gas. The TACA may be provided to flow with the solution to cycle through a CO.sub.2 capture system that includes an absorber and a stripper.

The composite amine absorbing solution according to the present invention absorbs CO.sub.2 or H.sub.2S or both in a gas, and is obtained by dissolving a linear monoamine, a diamine, and an amide group-containing compound in water. By adopting this composite amine absorbing solution, the composites are interacting in a composite manner, due to an integrated effect of the components, the absorption property of CO.sub.2 or H.sub.2S or both is favorable, the desorption properties of the CO.sub.2 or H.sub.2S absorbed when regenerating the absorbing solution become favorable, and the amount of steam from a reboiler used when regenerating the absorbing solution in a CO.sub.2 recovery device can be reduced.

A co-axial co-current contactor (CA-CCC) is described herein. The CA-CCC includes an outer annular support ring and an inner annular support ring configured to maintain the CA-CCC within an outer pipe and an inner pipe, respectively. The CA-CCC includes rich liquid flow channels located between the outer annular support ring and the inner annular support ring that are configured to allow a rich liquid stream to flow through the CA-CCC, and a central gas entry cone and gas flow channels configured to allow a gas stream to flow through the CA-CCC. The CA-CCC further includes radial blades configured to secure the central gas entry cone to the inner annular support ring and allow a lean liquid stream to flow into the central gas entry cone and the gas flow channels. The CA-CCC provides for efficient incorporation of liquid droplets formed from the lean liquid stream into the gas stream.

An absorbent liquid which absorbs at least one of CO.sub.2 and H.sub.2S from a gas, including a secondary linear monoamine; a tertiary linear monoamine or a sterically hindered primary monoamine; and a secondary cyclic diamine, wherein a concentration of each of the secondary linear monoamine, the tertiary linear monoamine or the sterically hindered primary monoamine; and the secondary cyclic diamine is less than 30% by weight.

A system and method for removing one or more predetermined gases from an environment is herein disclosed. An embodiment of the system and method will now be described. A means for conveying a fluid and a means for flowing the fluid is combined with adsorber and desorber sections. The fluid flows in the means for conveying the fluid by the means for flowing the fluid. Comparably, the fluid flows in the adsorber and desorber sections not by the means for flowing the fluid, but rather by capillary action. In the adsorber section, the environment is in direct contact with the fluid. The fluid is capable for adsorbing one or more gases from the environment. The fluid exits the adsorber section and subsequently flows into the desorber section. The desorber section is self-contained wherein an inner portion of the desorber section is not in direct contact with the environment. In the desorber section, the one or more gases are desorbed from the fluid into the inner portion of the desorber section. In an embodiment, the one or more gases exit the desorber section and the system as a whole.