An absorbent for the selective removal of hydrogen sulfide from a fluid stream comprising carbon dioxide and hydrogen sulfide, wherein the absorbent contains an aqueous solution, comprising: a) an amine or a mixture of amines of the general formula (I) wherein R.sup.1 is C.sub.1-C.sub.5-alkyl; R.sup.2 is C.sub.1-C.sub.5-alkyl; R.sup.3 is selected from hydrogen and C.sub.1-C.sub.5-alkyl; x is an integer from 2 to 10; and b) an ether or a mixture of ethers of the general formula (II): R.sup.4[OCH.sub.2CH.sub.2].sub.yOH; wherein R.sup.4 is C.sub.1-C.sub.5-alkyl; and y is an integer from 2 to 10; wherein R.sup.1 and R.sup.4 are identical; wherein the mass ratio of b) to a) is from 0.08 to 0.5. The absorbent is suitable for the selective removal of hydrogen sulfide from a fluid stream comprising carbon dioxide and hydrogen sulfide. The absorbent has a reduced tendency for phase separation at temperatures falling within the usual range of regeneration temperatures for the aqueous amine mixtures and is easily obtainable.

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The present invention relates to a dehydration composition and method of use thereof for drying gas streams, in particular natural gas streams, wherein the dehydration composition comprises (i) a glycol, (ii) a borate compound, (iii) an alkali metal carboxylate, and (iv) an additional glycol different than (i), and/or (v) an additional additive selected from an alkanolamine, a phosphate acid or salt compound, a sweetening agent, a low temperature viscosity improver, a corrosion inhibitor, an antifoaming agent, or mixtures thereof.

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.

The embodiments provide an acidic gas absorbent having low diffusibility, an acidic gas removal method, and an acidic gas removal apparatus. The acidic gas absorbent according to the embodiment comprises: an amine compound having a vapor pressure of 0.001 to 10 Pa at 20 C.; a water-soluble polymer compound having a mass-average molecular weight of 900 to 200000 and not containing a functional group having a pKa value greater than 7 except for hydroxy; and water.

The present invention relates to an aqueous alkanolamine solution and use therein a process for the selective removal of hydrogen sulfide from gaseous mixtures comprising hydrogen sulfide. The aqueous alkanolamine solution consists of an amino compound with the formula: R.sup.1R.sup.2NCH.sub.2CH(OH)CH.sub.2OH wherein R.sup.1 and R.sup.2 independently represent methyl, ethyl, propyl or isopropyl groups and bis(2-hydroxyethyl)methylamine, optionally one or more of a physical solvent, an antifoaming agent, an antioxidant, a corrosion inhibitor, a film former, a chelating agent or a pH adjuster and water The process for selectively removing hydrogen sulfide, comprising the step of contacting the gaseous mixture with the aqueous alkanolamine solution, preferably wherein the temperature of the aqueous alkanolamine solution is equal to or greater than 140 F.

The present invention includes a system and process to reduce amine mist emissions (or MEA) from carbon capture systems using colloidal gas aphrons (CGA), and includes a method for separating and recovering an amine solvent (e.g., in the form of entrained droplets/mist and/or fine aerosol particles) from a carbon dioxide scrubbed flue gas stream exiting a carbon capture system (e.g., oil-fired power plants, coal-fired power plants, and/or natural gas combined cycle plants).

A method of treating oil and gas streams including hydrogen sulfide (H.sub.2S) comprising treating the gas stream with an aqueous solution of an amine and a physical solvent which, when mixed in equal mass ratio with the amine or amine mixture, display a dielectric constant of at least about 20, wherein the pKa of the amine is at least about 9.0 and the amine boiling point is at least 200 C.

The present invention relates to an aqueous alkanolamine solution and use therein a process for the selective removal of hydrogen sulfide from gaseous mixtures comprising hydrogen sulfide. The aqueous alkanolamine solution consists ofan amino compound with the formula: R.sup.1R.sup.2NCH.sub.2CH(OH)CH.sub.2OH wherein R.sup.1 and R.sup.2 independently represent methyl, ethyl, propyl or isopropyl groupsand bis(2-hydroxyethyl)methylamine,optionally one or more of a physical solvent, an antifoaming agent, an antioxidant, a corrosion inhibitor, a film former, a chelating agent or a pH adjuster andwater The process for selectively removing hydrogen sulfide, comprising the step of contacting the gaseous mixture with the aqueous alkanolamine solution, preferably wherein the temperature of the aqueous alkanolamine solution is equal to or greater than 140 F.

Intensification techniques are described for enhancing biocatalytic CO.sub.2 absorption operations, and may include the use of a rotating packed bed, a rotating disc reactor, a zig-zag reactor or other reactors that utilize process intensification. Carbonic anhydrase can be deployed in the high intensity reactor free in solution, immobilized with respect to particles that flow with the liquid, and/or immobilized to internals, such as packing, that are fixed within the high intensity reactor.

The present invention relates to a dehydration composition and method of use thereof for drying gas streams, in particular natural gas streams, wherein the dehydration composition comprises (i) a glycol, (ii) a borate compound, (iii) an alkali metal carboxylate, and (iv) an additional glycol different than (i), and/or (v) an additional additive selected from an alkanolamine, a phosphate acid or salt compound, a sweetening agent, a low temperature viscosity improver, a corrosion inhibitor, an antifoaming agent, or mixtures thereof.