固载12-钨磷酸催化合成甲基丙烯酸叔丁酯

Synthesis of tertbutyl methacrylate catalyzed by supported 12-tungstophosphoric acid

制备了固载型 1 2 -钨磷酸 ( PW12 )催化剂 ,用其作甲基丙烯酸 ( MAA)和叔丁醇 ( TBA)的酯化催化剂 ,发现活性炭固载 PW12 ( PW12 / C)比 Si O2 或 Ti O2 固载 PW12 ( PW12 / Si O2 、PW12 / Ti O2 )的催化效果好。在 MAA与 TBA物质的量比为 1∶ 1 .1 5,催化剂用量约为反应物总质量的 1 .0 %、反应温度为1 1 5～ 1 2 0℃和反应时间 1 0 5min的条件下 ,酯化率达 89.4% ,产品纯度大于 98% 。

The supported 12-tungstophosphoric acid catalyst is prepared. It is used as the catalyst for esterification of methacrylic acid with tertbutyl alcohol in liquid-solid system. It is found that 12-tungstophoric acid / activated carbon (PW 12/C) as catalyst is superior to 12-tungstophoric acid / silicon dioxide or titanium dioxide catalytic activity. At the molar ratio of 1∶1.15 of methacrylic acid to tertbutyl alcohol; the total mass ratio of reactants to catalyst is 1%, temperature 115~120 ℃ and reaction time 105 min,the esterifiction conversion percentage is 89.4%, and the purity of the product is over 98%. The catalyst can be used repeatedly for many times without distinct loss in activity.