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.

A gas treatment device uses a gas to be treated which contains an acid compound that dissolves into water to produce acid and a treatment liquid which absorbs the acid compound to phase-separate, to separate an acid compound from the gas to be treated. The gas treatment device includes an absorber which brings the gas to be treated into contact with the treatment liquid; a regenerator 14 which heats the treatment liquid contacting the gas to be treated to separate an acid compound; and a liquid feeding portion which feeds the treatment liquid contacting the gas to be treated in the absorber to the regenerator. In the absorber, the treatment liquid contacting the gas to be treated phase-separates into a first phase portion having a high acid compound content and a second phase portion having a low acid compound content. The liquid feeding portion is configured to introduce, into the regenerator, the treatment liquid with the phase-separated first phase portion and second phase portion mixed.

To provide an aldehyde scavenger and a method for removing aldehydes by using the same, for quickly and continuously capturing aldehydes. An aldehyde scavenger comprising at least one O-substituted hydroxylamine or at least one chemically acceptable salt thereof, is used against an aldehyde generation source.

The embodiments provide an acidic gas absorbent, an acidic gas removal method using the absorbent, and an acidic gas removal apparatus using the absorbent. The absorbent absorbs an acidic gas in a large amount and is hardly diffused. The acidic gas absorbent according to the embodiment comprises an amine compound represented by the following formula (1):

##STR00001##

[In the formula, each R.sup.1 is independently hydrogen, an alkyl group, or a primary or secondary amino-containing aminoalkyl group provided that at least one of R.sup.1s is the aminoalkyl group, each R.sup.2 is independently hydrogen, an alkyl group, hydroxy, amino, hydroxyamino, or a primary or secondary amino-containing aminoalkyl group, the alkyl or aminoalkyl group contained in R.sup.1 or R.sup.2 has a straight-chain or branched-chain skeleton and may be substituted with hydroxy or carbonyl, and p is 2 to 4.]

A solvent system comprising a diluent and a nitrogenous base for the removal of CO.sub.2 from mixed gas streams is provided. Also provided is a process for removing CO.sub.2 from mixed gas streams using the disclosed solvent system. The solvent system may be utilized within a gas processing system.

A carbon dioxide absorbent composition is disclosed. Based on 100 parts by weight of the carbon dioxide absorbent composition, the carbon dioxide absorbent composition includes 5 to 45 parts by weight of sodium 2-[(2-aminoethyl)amino]ethanesulfonate. Moreover, a method for capturing carbon dioxide using the carbon dioxide absorbent composition is disclosed.

The present invention provides a carbon dioxide absorbent comprising a primary amine and a dialkylene glycol dialkyl ether or trialkylene glycol dialkyl ether. The carbon dioxide absorbent according to the present invention has an excellent carbon dioxide absorptivity, absorption rate and regeneration property.

Various embodiments of a portable carbon dioxide (CO2) absorption device that may remove excess CO2 from a closed environment are disclosed herein. The absorption device is reusable and configured for many environments.

A system and a process for capturing Carbon Dioxide (CO.sub.2) from flue gases are disclosed. The process comprises feeding a flue gas comprising CO.sub.2 to at least one Rotary Packed Bed (RPB) absorber rotating circularly. A solvent may be provided through an inner radius of the RPB absorber. The solvent may move towards an outer radius of the RPB absorber. The solvent may react with the flue gas in a counter-current flow. The process further includes passing the flue gas through at least one of a water wash and an acid wash to remove traces of the solvent present in the flue gas. Finally, the solvent reacted with the CO.sub.2 may be thermally regenerated for re-utilizing the solvent back in the process.

A carbon dioxide absorbent containing an amine compound (A) having a heterocyclic structure (X) selected from the group consisting of an oxygen-containing heterocyclic structure and a sulfur-containing heterocyclic structure, a content of the amine compound (A) being 65% by mass or more.