| 摘要 |
A process for the recovery of carbon dioxide, comprising: (a) an absorption step of bringing a carbon dioxide-containing gaseous feed stream into gas- liquid contact with an absorbing fluid, whereby at least a portion of the carbon dioxide present in the gaseous stream is absorbed into the absorbing fluid to produce (i) a refined gaseous stream having a reduced carbon dioxide content and (ii) an carbon dioxide-rich absorbing fluid, (b) a regeneration step of treating the carbon dioxide-rich absorbing fluid at a pressure of greater than 3 bar (absolute pressure) so as to liberate carbon dioxide and regenerate a carbon dioxide-lean absorbing fluid which is recycled for use in the absorption step, wherein the absorbing fluid is an aqueous amine solution containing a tertiary aliphatic alkanol amine and an effective amount of a carbon dioxide absorption promoter, the tertiary aliphatic alkanol amine showing little decomposition under specified conditions of temperature and pressure under co-existence with carbon dioxide. The tertiary aliphatic alkanol amine does not contain, in its molecular structure, a nitrogen atom that is substituted by more than one 2-hydroxyethyl moieties, or a nitrogen atom that is substituted by both a 2-hydroxyethyl moiety and a methyl moiety. Preferred tertiary aliphatic alkanol amines are selected from the group consisting of N-ethyl-diethanolamine, 2-(dimethylamino)-ethanol, 2- (diethylamino)-ethanol, 3-(dimethylamino)-1-propanol, 3-(diethylamino)-1- propanol, 1-(dimethylamino)-2-propanol, and 2-(diisopropylamino)-ethanol.
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