摘要:
The invention relates to a process for removing salts from an alkanolic reaction mixture which is obtained in the preparation of alkoxycarbonylaminotriazines and comprises at least one alkoxycarbonylaminotriazine, at least one cyclic and/or acyclic carbonic ester, at least one C1-C13-alkanol which optionally comprises one or two oxygen atoms as ether bonds and is optionally substituted by C1-C4-alkyl and/or hydroxyl, and also at least one alkali metal alkoxide or alkaline earth metal alkoxide, with or without melamine and with or without catalyst, in which salts are removed from the reaction mixture by ion exchange over a cation exchanger and/or anion exchanger.
摘要:
The invention relates to a process for preparing free-flowing, pulverulent alkoxycarbonylaminotriazine from an alkanolic reaction mixture which is obtained in the preparation of alkoxycarbonylaminotriazines and comprises at least one alkoxycarbonylaminotriazine, at least one cyclic and/or acyclic carbonic ester, at least one C1-C13-alkanol which optionally comprises one or two oxygen atoms in the form of ether bonds and is optionally substituted by C1-C4-alkyl and/or hydroxyl, and also at least one alkali metal or alkaline earth metal alkoxide, with or without melamine and with or without catalyst, by atomizing and drying the reaction mixture in a spray drier.
摘要:
The invention relates to a process for preparing free-flowing, pulverulent alkoxycarbonylaminotriazine from an alkanolic reaction mixture which is obtained in the preparation of alkoxycarbonylaminotriazines and comprises at least one alkoxycarbonylaminotriazine, at least one cyclic and/or acyclic carbonic ester, at least one C1-C13-alkanol which optionally comprises one or two oxygen atoms in the form of ether bonds and is optionally substituted by C1-C4-alkyl and/or hydroxyl, and also at least one alkali metal or alkaline earth metal alkoxide, with or without melamine and with or without catalyst, by atomizing and drying the reaction mixture in a spray drier.
摘要:
Processes comprising: providing an alkanolic reaction mixture, the alkanolic reaction mixture comprising: at least one alkoxycarbonylaminotriazine; at least one carbonic ester; at least one C1-C13-alkanol, which alkanol may further comprise up to two ether-bound oxygen atoms and may further comprise a substituent selected from the group consisting of C1-C4-alkyls and hydroxyls; and at least one alkali metal alkoxide or alkaline earth metal alkoxide; and subjecting the alkanolic reaction mixture to extraction with a polar extractant such that at least a portion of polar/ionic components present in the reaction mixture are removed, wherein the polar extractant is less than entirely miscible with an organic phase of the reaction mixture, to form an alkanolic phase comprising the at least one alkoxycarbonylaminotriazine and a polar phase comprising the polar extractant and the portion of polar/ionic components; and wherein the extraction is carried out with one or more selected from the group consisting of mixer/settler units, columns, centrifugal field separation extractors, and combinations thereof.
摘要:
An absorption medium for removing acid gases from a fluid stream comprises an aqueous solution of a) of at least one metal salt of an aminocarboxylic acid, and b) of at least one acid promoter, wherein the molar ratio of b) to a) is in the range from 0.0005 to 1.0. The acid promoter is selected from mineral acids, carboxylic acids, sulfonic acids, organic phosphonic acids and partial esters thereof. The absorption medium, compared with absorption media based on amino acid salts, has a reduced regeneration energy requirement without significantly reducing the absorption capacity of the solution for acid gases. In a process for removing acid gases from the fluid stream, the fluid stream is brought into contact with the absorption medium.
摘要:
An absorption medium for the removal of acid gases from a fluid stream comprises an aqueous solution a) of at least one amine and b) at least one phosphonic acid, wherein the molar ratio of b) to a) is in the range from 0.0005 to 1.0. The phosphonic acid is, e.g., 1-hydroxyethane-1,1-diphosphonic acid. The absorption medium exhibits a reduced regeneration energy requirement compared with absorption media based on amines or amine/promoter combinations, without significantly decreasing the absorption capacity of the solution for acid gases.
摘要:
A process for removing acid gases from a fluid stream in which a) the fluid stream is treated with an absorption liquid which comprises at least one amine, a stripping aid, and water, wherein the stripping aid is selected from water-miscible liquids, the boiling temperature of which at atmospheric pressure is lower than that of water, b) the treated fluid stream is treated with a liquid aqueous phase in order to convert entrained stripping aid at least in part to the aqueous phase, c) the loaded aqueous phase is heated in order to expel the stripping aid at least in part, and d) the regenerated aqueous phase is cooled and at least in part recycled to step b). The stripping aid promotes the regeneration of the absorbent by stripping. Emissions of the stripping aid via the treated fluid stream are avoided by the treated fluid stream being scrubbed with a liquid aqueous phase.
摘要:
An absorption medium for removing acid gases from a fluid stream comprises an aqueous solution of A) at least one cyclic amine compound having solely tertiary amine groups and/or sterically hindered secondary amine groups and B) at least one cyclic amine compound having at least one sterically unhindered secondary amine group. The absorption medium comprises, e.g., an aqueous solution of A) 1-hydroxyethylpiperidine and/or triethylenediamine and B) piperazine. The absorption medium is particularly suitable for separating off carbon dioxide from flue gases and satisfies the following criteria: (i) sufficient capacity at low CO2 partial pressures; (ii) sufficiently rapid absorption rate at low CO2 partial pressures; (iii) stability toward oxygen; (iv) low vapor pressure for reducing solvent losses; and (v) low energy requirement for regeneration of the absorption medium.
摘要:
A method for removing acid gases from a fluid stream comprises a) treating the fluid stream in an absorption zone with an absorption medium which comprises an aqueous solution of at least one amine, conducting the treated fluid stream through at least two scrubbing zones and treating it with a non-acidic aqueous phase in order to transfer entrained amine and/or entrained amine decomposition products at least in part to the aqueous phase, wherein aqueous phase is recycled via at least one scrubbing zone and aqueous phase is conducted through at least one scrubbing zone without recycling. The method permits efficient retention of amines from the treated fluid streams.
摘要:
Absorption medium for acid gases comprising an oligoamine (A) of the general formula (I) and a primary or secondary alkanolamine (B) of the general formula (II) in which the weight ratio of oligoamine (A) to the primary or secondary alkanolamine (B) is 0.2 to 4, and also the process for removing acid gases from a gas stream by contacting the gas stream at a pressure of 0.05 to 10 MPa abs with an aqueous solution brought to and maintained at a temperature of 20 to 80° C. of said absorption medium.