Abstract:
The present invention relates to a process for treating secondary components obtained in acrolein and/or (meth)acrylic acid production, comprising the steps of: a) contacting at least one wastewater stream (201) comprising at least a portion of the water of reaction removed in a first stage of a saturation column (101) with at least one process offgas stream (203), b) introducing energy by means of a first heat transferer (103) provided in a first saturation circuit (301) into the first stage of the saturation column (101), c) partly vaporizing the wastewater stream (201) into the process offgas stream (203) and passing the combined gas stream (205) into a second stage of the saturation column (101), d) drawing off a concentrated wastewater stream (207) from the bottom (1011) of the first stage of the saturation column (101) and feeding it to the top (1023) of the second stage of the saturation column (101), e) introducing energy by means of a second heat transferer (105) provided in a second circuit (303) into the second stage of the saturation column (101), f) partly vaporizing the concentrated wastewater stream (207) into the combined gas stream (205) to obtain an offgas stream (209), g) superheating the offgas stream (209), after it has been saturated, in a third heat transferer (113) to obtain a superheated offgas stream (211) and h) transferring the offgas stream (209) or the superheated offgas stream (211) from the saturation column (101) to a thermal aftertreatment. The present invention further relates to a plant (1) for treating the secondary components obtained in acrolein and/or (meth)acrylic acid production.
Abstract:
A process for continuously preparing a butyl acrylate H2C═CH—C(═O)OR, with R=n-butyl or isobutyl, wherein aqueous 3-hydroxypropionic acid is converted under dehydrating and esterifying conditions in the presence of the corresponding butanol R—OH in a reactor with a rectification column and butyl acrylate formed, unconverted butanol and water used and formed are distilled off overhead as a ternary azeotrope, after separation into a liquid aqueous phase and liquid organic phase each of the aqueous and organic phases is at least partly discharged, and the organic phase comprising the butyl acrylate and the butanol is subjected to distillative separation.
Abstract:
A composition for the immediate stopping of a free-radical polymerization comprises a) an inhibitor for the free-radical polymerization selected from among phenothiazines, b) an aprotic solvent and c) an ionic liquid. It serves to stabilize free-radically polymerizable monomers against free-radical polymerization. For the immediate stopping of free-radical polymerizations, the composition is added to a free-radically polymerizing system.
Abstract:
A process for preparing acrylic acid from ethylene oxide and carbon monoxide, in which ethylene oxide is carbonylated in an aprotic solvent with carbon monoxide in the presence of a cobalt catalyst system to give poly-3-hydroxypropionate, the cobalt content in the poly-3-hydroxypropionate formed is reduced with the aid of water and/or an aqueous solution as a precipitation and/or wash liquid, and the poly-3-hydroxypropionate is subsequently split by thermolysis to give acrylic acid.
Abstract:
The invention relates to a process for dehydrating aqueous 3-hydroxypropionic acid to acrylic acid in the liquid phase, wherein aqueous acrylic acid is removed continuously from the liquid phase and the liquid phase comprises an inert organic solvent 1.
Abstract:
A process for preparing acrylic acid from ethylene oxide and carbon monoxide, in which ethylene oxide is carbonylated in an aprotic solvent with carbon monoxide in the presence of a cobalt catalyst system to give poly-3-hydroxypropionate, the cobalt content in the poly-3-hydroxypropionate formed is reduced with the aid of water and/or an aqueous solution as a precipitation and/or wash liquid, and the poly-3-hydroxypropionate is subsequently split by thermolysis to give acrylic acid.
Abstract:
The invention relates to a process for dehydrating aqueous 3-hydroxypropionic acid to acrylic acid in the liquid phase, wherein aqueous acrylic acid is removed continuously from the liquid phase and the aqueous 3-hydroxypropionic acid and/or the liquid phase have a high content of oligomeric 3-hydroxypropionic acid.
Abstract:
The invention relates to a process for dehydrating aqueous 3-hydroxypropionic acid to acrylic acid in the liquid phase, wherein aqueous acrylic acid is removed continuously from the liquid phase and the liquid phase comprises an inert organic solvent 1.
Abstract:
The invention relates to a process for dehydrating aqueous 3-hydroxypropionic acid to acrylic acid in the liquid phase, wherein aqueous acrylic acid is removed continuously from the liquid phase and the aqueous 3-hydroxypropionic acid and/or the liquid phase have a high content of oligomeric 3-hydroxypropionic acid.