| 摘要 |
The present invention discloses a process for continuous preparation of (meth)acrylic acid alkyl esters by reacting (meth)acrylic acid with alkanols having from 1 to 8 carbon atoms in a solvent free homogeneous, liquid phase, at high temperature and in the presence of an acid esterification catalyst, wherein (meth)acrylic acid, alkanol, and the acid catalyst are fed to a reaction zone, water is removed by rectification during a permanence time as a mixture constituent which comprises an initial alcohol in a rectification unit (III) overlapped on reaction zone, the distilled product is separated into an organic phase comprising alkanol and an aqueous phase comprising water, the organic phase being essentially completely returned back to the rectification unit (III), the reaction mixture is removed from the reaction zone and transported to the distillation separation zone comprising additional rectification units, and the formed alkyl (meth)acrylate is separated therein. a) (Meth)acrylic acid and alkanol are reacted at a molar ratio of 1:0.75 to 1:2, b) a portion of the aqueous phase obtained in the upper part of the rectification unit (III) is returned back to the rectification unit, c) the reaction mixture removed from the reaction zone is fed to an additional rectification unit (I) and separated therein into a product (II) comprising a catalyst and a product (I) comprising (meth)acrylic acid alkyl ester, the remaining alkanol and (meth)acrylic acid, and d) product (I) is fed to the additional rectification unit (II), (meth)acrylic acid alkyl ester being separated therein from the remaining alkanol of the remaining (meth)acrylic acid, said remaining alkanol and said remaining (meth)acrylic acid being subsequently returned back to the reaction zone.
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