甲基丙烯醛氧化酯化制甲基丙烯酸甲酯

Preparation of Methyl Methacrylate by Oxidative Esterification of Methacrolein

制备了用于甲基丙烯醛(MAL)一步氧化酯化为甲基丙烯酸甲酯(MMA)的新型催化剂;考察了反应温度、催化剂在反应体系中的质量分数对MAL转化率和产物选择性的影响;将离子液体[bmim]PF6用于该反应中,不仅提高了产物的选择性,还能有效防止产物的聚合。反应温度θ=50℃,催化剂在反应体系中质量分数为2 4%,pH=10 5,O2流量6mL/min,反应时间6h时,在反应体系中添加1mL离子液体[bmim]PF6,MAL的转化率为96 2%,MMA单体的选择性可达98 7%。

A new type catalyst was prepared and applied to the oxidative esterification reaction of methacrolein (MAL) to methyl methacrylate (MMA).Ionic liquid [bmim]PF_6(1-butyl-3-methylimidazolium fluorophosphate) was used in this reaction,and it was found that the ionic liquid not only increased the selectivity for methyl methacrylate but also inhibited its polymerization.With 0.84 mL MAL,1 mL [bmim]PF_6 and w(catalyst)=2.4%,at reaction temperature 50 ℃,pH=10.5,O_2 flowrate 6 mL/min and reaction time 6 h,the MAL conversion and MMA selectivity reached 96.2% and 98.7% respectively.