A process for removing acid gases from a water vapor-containing fluid stream comprises a) providing an absorption liquid which is incompletely miscible with water; b) treating the fluid stream in an absorption zone with the absorption liquid to obtain an acid gas-depleted treated fluid stream and an acid gas-loaded absorption liquid; c) directing the treated fluid stream to a rehydration zone and treating the fluid stream with an aqueous liquid to volatilize at least part of the aqueous liquid; d) regenerating the loaded absorption liquid to expel the acid gases at least in part and obtain a regenerated absorption liquid, and directing the regenerated absorption liquid to step b); and e) separating, from the absorption liquid, an aqueous liquid that has condensed in the absorption zone, and directing the aqueous liquid to step c). The process allows for an efficient removal of water accumulated in the absorption liquid system.

A method for separating carbon dioxide (CO.sub.2) from a gas stream is provided. The method includes reacting at least a portion of CO.sub.2 in the gas stream with a plurality of liquid sorbent particles to form a plurality of solid adduct particles and a first CO.sub.2-lean gas stream; the solid adduct particles entrained in the first CO.sub.2-lean gas stream to form an entrained gas stream. The method includes separating at least a portion of the plurality of solid adduct particles from the entrained gas stream in a separation unit to form an adduct stream and a second CO.sub.2-lean gas stream. The method further includes heating at least a portion of the adduct stream in a desorption unit to form a CO.sub.2 stream and a regenerated liquid sorbent stream. A system for separating CO.sub.2 from a gas stream is also provided.

An amino-siloxane composition is presented. The amino-siloxane composition includes structure (I): ##STR00001##
wherein R.sup.1 is independently at each occurrence a C.sub.1-C.sub.5 aliphatic radical; R.sup.2 is a C.sub.3-C.sub.4 aliphatic radical; R.sup.3 is a C.sub.1-C.sub.5 aliphatic radical or R.sup.4, wherein R.sup.4 comprises structure (II): ##STR00002##
and
X is an electron donating group. Methods of reducing an amount of carbon dioxide in a process stream using the amino-siloxane composition are also presented.

A process capturing CO.sub.2 from a CO.sub.2-containing gas stream, contacting a CO.sub.2-containing gas stream with a CO.sub.2-absorbing agent in an absorption step in a vessel with maximum temperature T1 resulting in absorption of CO.sub.2. The CO.sub.2 absorbing agent comprising a polymer dissolved in an aqueous medium, the polymer, a thermoresponsive copolymer, comprising amine monomer distributed through the copolymer, subjecting the CO.sub.2-containing absorbing agent to a desorption step in a vessel with maximum temperature T2, releasing CO.sub.2, wherein T1 is below LCST of the thermoresponsive polymer at maximum CO.sub.2 loading, and T2 is above LCST of the thermoresponsive polymer at minimum CO.sub.2 loading. CO.sub.2 absorbing agent comprises amine component dissolved in the aqueous medium. Use of the specific polymer dissolved in an aqueous medium at T1, wherein amine monomer, distributed through the copolymer with an amine component, improves net CO.sub.2 sorption and high absorption speed, allowing a relatively small absorption reactor.

A method for treatment of a flue gas involves feeding the flue gas and a lean solvent to an absorber. The method further involves reacting the flue gas with the lean solvent within the absorber to generate a clean flue gas and a rich solvent. The method also involves feeding the clean flue gas from the absorber and water from a source, to a wash tower to separate a stripped portion of the lean solvent from the clean flue gas to generate a washed clean flue gas and a mixture of the water and the stripped portion of the lean solvent. The method further involves treating at least a portion of the mixture of the water and the stripped portion of the lean solvent via a separation system to separate the water from the stripped portion of the lean solvent.

The object is to prevent deterioration and loss of dicyanobenzene in producing dicyanobenzene by ammoxidation of xylene to thereby achieve industrial and economical advantage in producing of dicyanobenzene. The method for producing dicyanobenzene of the present invention includes: contacting a xylene-ammoxidation reaction gas containing dicyanobenzene in ammoxidation of xylene with an organic solvent so as to obtain a dicyanobenzene-absorbing solution; contacting the dicyanobenzene-absorbing solution with a basic aqueous solution containing a salt such as ammonium carbonate so as to extract a water-soluble salt formed by neutralization reaction between carboxylic acid in the dicyanobenzene-absorbing solution and a base in the basic aqueous solution into an aqueous phase; separating the mixture of the dicyanobenzene-absorbing solution and the basic aqueous solution into an organic phase and an aqueous phase; decomposing the salt such as ammonium carbonate contained in the organic phase for separation of the salt from the organic phase; and distilling the organic phase to separate low boiling point compounds contained in the organic phase from the organic phase so as to obtain dicyanobenzene.

A flue gas stream arising from fossil fuel fired sources containing nitrogen oxide contaminants is conveyed through an exhaust duct into a quencher. In the quencher aqueous medium is sprayed into contact with the flue gas stream. The quenched flue gas stream is mixed with ozone distributed at a high velocity in a sub-stoichiometric amount for partial oxidation of NO.sub.xto form NO.sub.2 and prevent the formation of N.sub.2O.sub.5. The flue gas containing NO.sub.2 is absorbed into an acidic medium of a wet scrubber to form nitrous acid. In the scrubber the nitrous acid is mixed with selected compounds of ammonia to decompose the nitrous acid for release of nitrogen. With this process the consumption of ozone and the operating costs associated therewith eliminate the requirement to dispose of nitrate recovered from the scrubber purge stream.

Disclosed are a compound including an oxalate, a carbon dioxide absorbent including the same, a method of preparing the carbon dioxide absorbent and a method of removing carbon dioxide, which may overcome issues of high recycling energy and low absorptivity of a conventional carbon dioxide absorbent to considerably reduce recycling energy and absorb a greater amount of carbon dioxide per unit absorbent, so that a size of a carbon dioxide absorption tower may be reduced and a less amount of recycling energy may be used, contributing to a substantial decrease in device manufacture costs and management costs.

Provided is a composite semipermeable membrane, comprising: a microporous support membrane which comprises a substrate and a porous support, and a polyamide separation functional layer formed on the microporous support membrane, wherein the polyamide has an irreversible heat absorption, which is measured using temperature modulated DSC, of 275 J/g or more at a temperature in the range of 20 to 150 C. in the first heating process.

Provided is a high-performance composite semipermeable membrane having high chemical durability, high water permeation and high rejection.

The invention is directed to a method and an apparatus for absorption of terpenes from methane comprising gas streams.

The method for absorbing terpenes from a methane comprising gas stream, comprises the step of contacting said stream with a liquid that comprises water and a terpene absorbing agent thereby producing a terpene rich liquid.