| 摘要 |
PURPOSE:To obtain methyl (meth)acrylate in high purity and yield, by distilling crude methyl (meth)acrylate in contact with an acidic catalyst, thereby decomposing and regenerating the beta-methoxy-propionaldehyde produced as a by-product during the esterification reaction. CONSTITUTION:The crude methyl (meth)acrylate obtained by the oxidative esterification of (meth)acrolein with an oxygen-containing gas in methanol in the presence of a catalyst, is distilled at 55-130 deg.C, preferably 55-110 deg.C in contact with an acidic catalyst (e.g. benzenesulfonic acid, toluenesulfonic acid, etc.). The beta-methoxypropionaldehyde or beta-methoxyisobutylaldehyde or dimethyl acetal of (meth)acrolein produced as a by-product during the reaction is decomposed and regenerated to (meth)acrolein and methanol by this process, and purified methyl (meth)acrylate can be obtained. The decomposed and regenerated product is separated as a low-boiling fraction, and recycled and reused. |
