Abstract: The invention relates to a process and a plant for removal of acidic gas constituents from synthesis gas by absorption in a physical scrubbing medium. A first scrubbing medium laden with at least carbon dioxide (CO2) is supplied to a decompression vessel for depressurization from a first absorption apparatus via a first feed conduit. Furthermore, a second scrubbing medium laden with at least carbon dioxide (CO2) is supplied to the decompression vessel for depressurization from a second absorption apparatus via a second feed conduit. The carbon dioxide concentration in the first laden scrubbing medium is higher than the carbon dioxide concentration in the second laden scrubbing medium.

Abstract: The present invention relates to a process for producing surface-reacted calcium carbonate, wherein a calcium carbonate-comprising material is treated with phosphoric acid, carbon dioxide, and specific dicarboxylic acids, in an aqueous medium to form an aqueous suspension of surface-reacted calcium carbonate. Furthermore, the present invention relates to surface-reacted calcium carbonate obtained by said process and its use.

Abstract: An acid gas removal apparatus includes a reclaimer control device that performs: first supply water control in which at least one of reflux water, steam condensate, and desalinated water is supplied to a reclaimer as first supply water, at non-volatile component removal reclaiming; second supply water control in which at least one of the reflux water, the steam condensate, and the desalinated water is supplied to the reclaimer, and a washing liquid including an acid gas absorbing liquid is supplied to the reclaimer as second supply water, at an initial stage of finish reclaiming; and third supply water control in which supply of the second supply water is stopped and at least one of the reflux water, the steam condensate, and the desalinated water is supplied as the first supply water, at a later stage of the finish reclaiming.

Abstract: A process for treating an H2S- and CO2-comprising fluid stream, in which a) the fluid stream is treated in a first absorber at a pressure of 10 to 150 bar with a first substream of a regenerated H2S-selective absorbent to obtain a treated fluid stream and an H2S-laden absorbent; b) the H2S-laden absorbent is heated by indirect heat exchange with regenerated H2S-selective absorbent; c) the heated H2S-laden absorbent is decompressed to a pressure of 1.

Abstract: Methods and systems for producing calcium carbonate from calcium hydroxide and carbon dioxide are disclosed herein. In some embodiments, a method for producing calcium carbonate comprises (i) providing a first plurality of particles comprising solid-state calcium hydroxide, and (ii) introducing a gas stream comprising carbon dioxide to the first plurality of particles to produce a second plurality of particles comprising calcium carbonate. Individual ones of the first plurality of particles can include a specific surface area of at least 20 m2/g and a free moisture content of from 2% to 20%. The second plurality of particles comprising calcium carbonate are not produced via precipitation.

Abstract: Embodiments of the present disclosure describe methods of removing one or more compounds from a fluid comprising contacting a metal-organic framework (MOF) composition having a square-octahedral topology with a fluid containing one or more of CH4 and O2, sorbing one or more of CH4 and O2 with the MOF composition, and storing one or more of the CH4 and O2 with the MOF composition.

Abstract: The present disclosure relates to methods of synthesizing slurries comprising ferrihydrite nanoparticles, and systems and methods employing the same. The method may include the steps of preparing an aqueous solution having ferric iron cations, halide anions, and a two-line iron promoter, and precipitating the ferrihydrite nanoparticles in the aqueous solution, thereby producing a ferrihydrite slurry. The ferrihydrite slurries may be useful in treating a polluted fluid having sulfur contaminants therein.

Abstract: A process and system are disclosed for capturing carbon dioxide from a gas stream. The process and system comprise a first stage, in which a metal silicate is reacted with nitric acid to produce a metal nitrate. The metal silicate can be one or more of: an alkaline-earth metal silicate, in particular magnesium or calcium; or an alkali metal silicate, in particular lithium. The process and system also comprise a second stage, in which the metal nitrate from the first stage is heated to a temperature sufficient to decompose the metal nitrate to a metal oxide. The process and system further comprise a third stage, in which the metal oxide is mixed with water to convert the metal oxide to a metal hydroxide solution. The process and system additionally comprise a fourth stage, in which the gas stream is scrubbed with the solution from the third stage such that the metal hydroxide reacts with the carbon dioxide to form a metal carbonate/bicarbonate product.

Abstract: An absorbent liquid which absorbs at least one of CO2 and H2S 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.

Abstract: Provided herein are metal organic frameworks comprising metal nodes and N-donor organic ligands which have high selectivity and stability in the present of gases and vapors including H2S, H2O, and CO2. Methods include capturing one or more of H2S, H2O, and CO2 from fluid compositions, such as natural gas.

Abstract: Disclosed herein are acid gas absorbents that afford high acid gas (CO2) absorption amount per unit volume and high absorption speed and can prevent the absorbent components from diffusing. Also disclosed herein is a method and device for removing an acid gas, in which the energy required for separating the acid gas and regenerating the absorbent is reduced, are provided.

Abstract: Provided herein are metal organic frameworks comprising metal nodes and N-donor organic ligands. Methods for capturing chemical species from fluid compositions comprise contacting a metal organic framework characterized by the formula [MaMbF6-n(O/H2O)w(Ligand)x(solvent)y]z with a fluid composition and capturing one or more chemical species from the fluid composition.

Abstract: The embodiments provide an acidic gas absorbent, an acidic gas removal method, and an acidic gas removal apparatus. The absorbent absorbs an acidic gas in a large amount and hardly diffuses in air. The acidic gas absorbent according to the embodiment comprises an amine compound having a sulfonyl group and two or more amino groups.

Abstract: The disclosure provides for multivariant zeolitic imidazolate frameworks (ZIFs), methods of making thereof, and methods of use therefrom.

Abstract: 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.

Abstract: Carbon dioxide is separated from a flue gas by scrubbing the gas with an aqueous solution of an amine and a salt, the CO2 is thereafter released from the solution by heating. The scrubbing step is performed with a co-current gravity fed stream of an aqueous solution of the amine and a salt of the gas and solution through an absorption column.

Abstract: The invention pertains to processes for separating water from air. The processes may employ using an LCST solution with or without subsequent reverse osmosis, nanofiltration, or ultrafiltration.

Abstract: Embodiments described herein provide methods of operating a linear contactor for absorbing contaminants from a gas stream. The gas stream flows from a first end to a second end of the linear contactor. Fresh absorbent is provided at the first end of the linear contactor based on the theoretical minimum amount of absorbent needed to remove the contaminants. Absorbent is recycled from the second end to the first end of the linear contactor. Fresh absorbent is provided at the second end based on chemical condition of the recycled absorbent. Apparatus for practicing the method is also described.

Abstract: A method for removing hydrogen sulfide from a biogas, wherein the hydrogen sulfide is absorbed in an aqueous liquid to produce a cleaned gas having a reduced amount of hydrogen sulfide relative to the biogas. The aqueous liquid is subsequently treated by contacting with a sulfur dye or sulfurized vat dye in the presence of an oxidizer such as oxygen gas, to convert the sulfides in the aqueous liquid to a non-toxic, water-soluble, product.

Abstract: A composite material for purifying air includes a porous foam material which is an open-cell polyurethane foam net; and a mixture sprayed on the interior and/or the surface of the porous foam material, the mixture including an absorbent material, a treating agent and an adhesive; wherein the adsorptive material is diatomite, and the treating agent is alkali solution.