Disclosed is an absorbing liquid for separating and capturing carbon dioxide from a carbon dioxide-containing gas, the absorbing liquid containing: at least one alkanolamine represented by formula (1) ##STR00001##
wherein R.sup.1 represents hydrogen or C.sub.1-4 alkyl, R.sup.2 and R.sup.3 are identical or different and each represent hydrogen or C.sub.1-3 alkyl, R.sup.1, R.sup.2, and R.sup.3 are not all hydrogen, and n is 1 or 2; a low-molecular-weight diol compound and/or glycerin; and water.

Solvent absorption processes for separating components of an impure feed gas are disclosed. The processes involve two stages of gas purification. The acid gases including hydrogen sulfide, carbon dioxide and other sulfur compounds are simultaneously removed from the feed gas by contact with a physical solvent in two stages. The subject matter disclosed provides improved processes to reduce the operating costs of the system.

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.

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.

##STR00001##

Disclosed is a carbon dioxide absorbent and a carbon dioxide separation method using the same that greatly reduces energy consumption due to a small amount of latent heat required in regeneration of absorbents, enhances CO.sub.2 absorption rate, undergoes almost no thermal denaturation even at high temperatures while absorbing carbon dioxide, and results in a considerable reduction of the cost associated with absorption of carbon dioxide.

The present disclosure relates to a porous liquid or a porous liquid enzyme 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 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.

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 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.

The present disclosure provides a method for the separation of a gas constituent from a gaseous mixture. The disclosure also provides polyethylene glycol disubstituted siloxane based solvents for use in the method. These solvents are of use for pre-combustion CO.sub.2 capture and are capable of replacing glycol-based solvents while offering operation at a higher temperature region. These solvents are also of use for generation of hydrogen from reformed natural gas or syngas, adjusting CO/H.sub.2 ratio for Coal & Biomass to Liquids, removal of CO.sub.2 from syngas for coal & biomass to NH.sub.3/Fertilizer, natural gas sweetening, and upgrading of landfill and biogas.