Systems and methods for separating carbon dioxide (CO.sub.2) from a gas stream are provided. The system includes a reaction chamber 20, a pressurization unit 30, and a desorption unit 40. The reaction chamber 20 is configured to receive a liquid sorbent stream 14 and the gas stream 12, to react at least a portion of CO.sub.2 in the gas stream 12 with the liquid sorbent and form an adduct stream 22. The pressurization unit 30 is configured to contact the adduct stream 22 with a pressurized CO.sub.2 stream 24 and form a pressurized adduct stream 32 that includes a liquid CO.sub.2 adduct. The desorption unit 40 is in fluid communication with the pressurization unit 30, and is configured to decompose at least a portion of the liquid CO.sub.2 adduct to form a CO.sub.2 stream 42 and a regenerated liquid sorbent stream 44.

An aqueous ionic absorbent solution is disclosed containing (a) about 15 wt. % to about 80 wt. % of one or more diluents, based on the total weight of the aqueous ionic absorbent solution; and (b) an ionic absorbent containing a cation and an anion comprising an amine moiety.

Systems and methods for separating carbon dioxide (CO.sub.2) from a gas stream are provided. The system includes a reaction chamber 20, a pressurization unit 30, and a desorption unit 40. The reaction chamber 20 is configured to receive a liquid sorbent stream 14 and the gas stream 12, to react at least a portion of CO.sub.2 in the gas stream 12 with the liquid sorbent and form an adduct stream 22. The pressurization unit 30 is configured to contact the adduct stream 22 with a pressurized CO.sub.2 stream 24 and form a pressurized adduct stream 32 that includes a liquid CO.sub.2 adduct. The desorption unit 40 is in fluid communication with the pressurization unit 30, and is configured to decompose at least a portion of the liquid CO.sub.2 adduct to form a CO.sub.2 stream 42 and a regenerated liquid sorbent stream 44.

Methods and compositions useful, for example, for physical solvent carbon capture. A method comprising: contacting at least one first composition comprising carbon dioxide with at least one second composition to at least partially dissolve the carbon dioxide of the first composition in the second composition, wherein the second composition comprises at least one siloxane compound which is covalently modified with at least one non-siloxane group comprising at least one heteroatom. Polydimethylsiloxane (PDMS) materials and ethylene-glycol based materials have high carbon dioxide solubility but suffer from various problems. PDMS is hydrophobic but suffers from low selectivity. Ethylene-glycol based systems have good solubility and selectivity, but suffer from high affinity to water. Solvents were developed which keep the desired combinations of properties, and result in a simplified, overall process for carbon dioxide removal from a mixed gas stream.

In a method of absorbing CO.sub.2 from a gas mixture the use of an absorption medium comprising water and at least one amine of formula (I) ##STR00001## where R.sup.1 is a (CH.sub.2).sub.n(XCH.sub.2CH.sub.2).sub.mYR.sup.3 radical where R.sup.3=hydrogen or an alkyl radical having from 1 to 6 carbon atoms, X and Y are each, independently of one another, NR.sup.3, oxygen, SO or SO.sub.2, where in the case of YSO and in the case of YSO.sub.2, R.sup.3 is not hydrogen, and YR.sup.3 can be an N-morpholinyl radical or an N-piperazyl radical, n=2 to 4, m=0 to 4 and R.sup.2 is hydrogen, an alkyl radical having from 1 to 6 carbon atoms or a radical R.sup.1, where m is not 0 when R.sup.2 is not a radical R.sup.1, YNR.sup.3 and YR.sup.3 is not an N-morpholinyl radical and not an N-piperazyl radical, makes it possible to avoid precipitation of a solid during the absorption of CO.sub.2 and a separation into two liquid phases during the regeneration of the absorption medium.

The invention relates to an absorbent solution and to a method of removing acid compounds contained in a gaseous effluent, comprising water and at least one of the following two nitrogen compounds belonging to the family of tertiary diamines: 1-dimethylamino-3-(2-dimethylaminoethoxy)-2-propanol

##STR00001## 1,1-oxybis[3-(dimethylamino)-2-propanol]

##STR00002##

Disclosed herein are scavenging compounds and compositions useful in applications relating to the production, transportation, storage, and separation of crude oil and natural gas. Also disclosed herein are methods of using the compounds and compositions as scavengers, particularly in applications relating to the production, transportation, storage, and separation of crude oil and natural gas.

This invention provides novel compositions comprising substituted polyamines as acid gas scrubbing solutions and methods of using the compositions in an industrial system. The invention relates to the use of such polyamine compounds in industrial processes to remove acidic contaminants from natural and industrial fluid streams, such as natural gas, combustion gas, natural gas, synthesis gas, biogas, and other industrial fluid streams. The compositions and methods of the invention are useful for removal, absorption, or sequestration of acidic contaminants and sulfide contaminants including CO.sub.2, H.sub.2S, RSH, CS.sub.2, COS, and SO.sub.2.

The present disclosure relates to a porous liquid or a porous liquid enzyme system that includes a high surface area solid and a liquid film substantially covering the high surface area solid. The porous liquid or porous liquid enzyme may be contacted with a fluid that is immiscible with the liquid film such that a liquid-fluid interface is formed. The liquid film may facilitate mass transfer of a substance or substrate across the liquid-fluid interface. The present disclosure also provides methods of performing liquid-based extractions and enzymatic reactions utilizing the porous liquid or porous liquid enzyme of the present disclosure. The present disclosure also provides methods for selecting the components of the porous liquid or a porous liquid enzyme system and methods of self-replenishing the used liquid coating.