The present invention is related to a method for determination of unit operations of a chemical plant for acid gas removal, the method carried out by a computer or a distributed computer system and the method comprising the steps of: providing a first set of parameters for the unit operations; providing a second set of parameters for the unit operations based on the provided first set of parameters and based on data retrieved from a database; determining a digital model of the chemical plant based on the first set of parameters and the second set of parameters, wherein the digital model comprises a system of equations defining the unit operations of the chemical plant; selecting starting points for an equation-based solution method of the system of equations, wherein the starting points are at least partially selected from the: (i) the first set of parameters; (ii) the second set of parameters; and (iii) the data retrieved from the database; determining resultant settings for the unit operations of the chemical plant using the equation-based solution method for the system of equations initialized by the selected starting points.

A method for removing carbon dioxide from a gaseous source, the method comprising: (i) contacting said gaseous source with an aqueous solution of a carbon dioxide sorbent that reacts with carbon dioxide to form an aqueous-soluble carbonate or bicarbonate salt of said carbon dioxide sorbent; (ii) contacting the aqueous solution from step (i) with a bis-iminoguanidine carbon dioxide complexing compound, which is different from the carbon dioxide sorbent, to result in precipitation of a carbonate or bicarbonate salt of said carbon dioxide complexing compound and regeneration of the carbon dioxide sorbent; and (iii) removing the precipitated carbonate or bicarbonate salt from the aqueous solution in step (ii) to result in a solid form of said carbonate or bicarbonate salt of the carbon dioxide complexing compound. The method may further include a step (iv) of regenerating the carbon dioxide complexing compound by subjecting the precipitated salt to sufficient heat and/or vacuum.

An improved process for deacidizing a gaseous mixture with reduced overall energy costs is described. The process involves contacting the gaseous mixture with at least one of a vaporizing compound, a vaporized compound, a vaporizing solution of compound and a vaporized solution of compound, and forming a liquid or solid reaction product that can be easily separated from the gaseous mixture.

The use of an amine of the formula (I)

##STR00001##

in which the R.sup.1 to R.sup.5 radicals are each as defined in the description, and an absorbent and a process for removing acidic gases from a fluid stream, especially for selectively removing hydrogen sulfide over carbon dioxide. The invention also relates to particular amines suitable for selective removal of hydrogen sulfide. Absorbents based on amines of the formula (I) have high selectivity, high loading capacity and good regeneration capacity.

The use of an amine of the formula (I) ##STR00001##
in which the R.sup.1 to R.sup.5 radicals are each as defined in the description, and an absorbent and a process for removing acidic gases from a fluid stream, especially for selectively removing hydrogen sulfide over carbon dioxide. The invention also relates to particular amines suitable for selective removal of hydrogen sulfide. Absorbents based on amines of the formula (I) have high selectivity, high loading capacity and good regeneration capacity.

The embodiment provides an acidic gas absorbent. The acidic gas absorbent comprises an amine compound of the formula (1) and a cyclic amino compound of the formula (2) or (3):

##STR00001##

[In the formulas, each R.sup.1 is independently a straight-chain hydroxyalkyl having a hydroxy at the terminal; R.sup.2 is a branched-chain secondary alkyl group; R.sup.3 and R.sup.4 are hydrogen, hydroxy, a hydroxyalkyl or aminoalkyl, provided that at least one of R.sup.3 and R.sup.4s is a hydroxyalkyl or aminoalkyl; each p is independently an integer of 2 to 4; each R.sup.5 is independently hydrogen, hydroxy, or a hydroxyalkyl or aminoalkyl, provided that at least one of R.sup.5s is a hydroxyalkyl or aminoalkyl; and q is an integer of 3 to 8.]

The acidic gas removal method and apparatus according to the embodiment uses the above acidic gas absorbent.

An aqueous solvent composition is provided, comprising a nucleophilic component having one or more sterically unhindered primary or secondary amine moieties, a Brnsted base component having one or more basic nitrogen moieties, a water-soluble organic solvent, and water. A biphasic composition is provided, comprising one or more carbamate compounds, one or more conjugate acids of Brnsted base, a water-soluble organic solvent, and water. A biphasic CO.sub.2 absorption process is also provided, utilizing the biphasic solvent composition.

An aromatic imine blend includes an aromatic imine and a de-foaming agent, surfactant, amine, hydrotrope, alcohol, amino acid, ether, alkalinity stabilizer, or a combination thereof. A process of removing carbon dioxide or a sulfide from oil, water, or natural gas includes supplying an oil, water, or natural gas stream and contacting the oil, water, or natural gas stream with an aromatic amine blend. The aromatic imine blend includes an aromatic imine and a de-foaming agent, surfactant, amine, hydrotrope, alcohol, amino acid, ether, alkalinity stabilizer, or a combination thereof.

The present invention relates to methods for improving carbon capture using entrained catalytic-particles within an amine solvent. The particles are functionalized and appended with a CO.sub.2 hydration catalyst to enhance the kinetics of CO.sub.2 hydration and improve overall mass transfer of CO.sub.2 from an acid gas.

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.