Abstract: A process for separating off acid gases from a nitrogen oxide-comprising fluid stream, wherein a) the fluid stream is brought into contact in an absorption zone with an aqueous absorbent which comprises at least one amino group-comprising compound, wherein a deacidified fluid stream is obtained, b) the deacidified fluid stream is brought into contact in at least one scrubbing zone with an aqueous scrubbing liquid and a de-aminated deacidified fluid stream is obtained, wherein the scrubbing liquid is recycled via at least one scrubbing zone, c) overflow from the at least one scrubbing zone is treated with UV light, and d) the UV-treated overflow is combined with the absorbent. The process permits the efficient degradation of the nitrosamines present in the absorbent.

Abstract: A description is given of an absorption medium for removing carbon dioxide from gas streams which comprises aqueous solution of an amine of the formula I HNR2??(I) where one or both radicals R are and the other radical R is hydrogen. The absorption medium is distinguished by particular oxidation resistance.

Abstract: A description is given of an absorption medium for removing carbon dioxide from a gas stream, which comprises an aqueous solution of at least one amine and at least one aminocarboxylic acid and/or aminosulfonic acid. The concomitant use of an aminocarboxylic acid or aminosulfonic acid reduces the energy required for regeneration of the absorption medium.

Abstract: A description is given of a process for removing carbon dioxide from gas streams in which the partial pressure of the carbon dioxide is less than 200 mbar, in particular flue gases, the gas stream being contacted with a liquid absorption medium which comprises an aqueous solution (A) of a tertiary aliphatic alkanolamine and (B) an activator of the formula R1—NH—R2—NH2, where R1 is C1-C6-alkyl and R2 is C2-C6-alkylene, the sum of the concentrations of A and B being 2.5 to 7 mol/l, and the molar ratio of B to A being in the range of 1:3 to 1.5:1. The activator is, for example, 3-methylaminopropylamine, the tertiary aliphatic amine methyldiethanolamine, methyldiisopropanolamine or n-butyldiethanolamine. The process permits substantial removal of carbon dioxide and the regeneration of the absorption medium is possible with relatively low energy consumption.

Abstract: An absorption medium for deacidifying fluid streams which has improved oxidation stability includes at least one aliphatic amine, and at least one non-hydroquinoid antioxidant. The absorption medium may be employed in deacidifying a fluid stream, in particular an oxygen-containing fluid stream, when the fluid stream is brought into intimate contact with the absorption medium in at least one absorption step.

Abstract: A description is given of an absorption medium for removing carbon dioxide from a gas stream, which comprises an aqueous solution of at least one amine and at least one aminocarboxylic acid and/or aminosulfonic acid. The concomitant use of an aminocarboxylic acid or aminosulfonic acid reduces the energy required for regeneration of the absorption medium.

Abstract: A description is given of a process for removing carbon dioxide from gas streams in which the partial pressure of the carbon dioxide is less than 200 mbar, in particular flue gases, the gas stream being contacted with a liquid absorption medium which comprises an aqueous solution (A) of a tertiary aliphatic alkanolamine and (B) an activator of the formula R1—NH—R2—NH2, where R1 is C1-C6-alkyl and R2 is C2-C6-alkylene, the sum of the concentrations of A and B being 2.5 to 7 mol/l, and the molar ratio of B to A being in the range of 1:3 to 1.5:1. The activator is, for example, 3-methylaminopropylamine, the tertiary aliphatic amine methyldiethanolamine, methyidiisopropanolamine or n-butyldiethanolamine. The process permits substantial removal of carbon dioxide and the regeneration of the absorption medium is possible with relatively low energy consumption.

Abstract: A description is given of an absorption medium for removing carbon dioxide from gas streams which comprises aqueous solution of an amine of the formula I HNR2 ??(I) where one or both radicals are and the other radical R is hydrogen. The absorption medium is distinguished by particular oxidation resistance.

Abstract: The invention relates to a method for the removal of carbon dioxide from a gas flow, in which the partial pressure of the carbon dioxide in the gas flow is less than 200 mbar, whereby the gas flow is brought into contact with a liquid absorption agent, comprising an aqueous solution (A) of a tertiary aliphatic amine and (B) an activator of general formula R1-NH-R2-NH2, where R1=C1-C6 alkyl and R2=C2-C6 alkylene. The method is particularly suitable for treatment of flue gases and also relates to an absorption agent.

Abstract: The invention relates to a method for the removal of carbon dioxide from a gas flow with a carbon dioxide partial pressure in the gas flow of less than 200 mbar, whereby the gas flow is brought into contact with a liquid absorption agent, selected from an aqueous solution (A) of an amino compound with at least two tertiary amino groups in the molecule and (B) an activator, selected from the primary and secondary amines, or (A) a tertiary aliphatic amine, the reaction enthalpy ?RH for the protonation of which is greater than that for methyldiethanolamine and (B) an activator, selected from 3-methylaminopropylamine, piperazine, 2-methylpiperazine, N-methylpiperazine, homopiperazine, piperidine and morpholine. The method is particularly suitable for the treatment of flue gases and also relates to an absorption agent.

Abstract: A description is given of an absorption medium for deacidifying fluid streams which has improved oxidation stability and comprises at least one aliphatic amine, in particular an alkanolamine, and at least one non-hydroquinoid antioxidant. The absorption medium serves for deacidifying a fluid stream, in particular an oxygen-containing fluid stream, the fluid stream being brought into intimate contact with the absorption medium in at least one absorption step.