改性HM催化剂上2-甲基萘的择形异丙基化反应

 采用等体积浸渍法制备了不同含量CeO2和MgO复合改性的HM催化剂，以2-甲基萘与异丙醇的异丙基化反应为探针，在固定床反应器上考察其催化性能。结果表明，2-甲基萘择形异丙基化反应的最佳条件是反应压力2 MPa、反应温度200℃、n(2-MN): n(i-PrOH): n(Cyclohexane)=1: 3: 70。在20%质量分数的CeO2改性后的HM催化剂上，在上述最佳反应条件下反应8 h后，2-甲基萘的转化率为37.7%，目的产物2-甲基-6-异丙基萘(2,6-MIPN)的选择性和产率分别为83.0%和28.7%；在加入少量MgO复合改性后的HM催化剂上，2,6-MIPN的选择性达到89.5%。CeO2和MgO的复合改性使分子筛内、外表面的强酸酸量减少，抑制了非择形催化反应的发生，提高了2-甲基-6-异丙基萘的选择性。

SHAPE-SELECTIVE ISOPROPYLATION OF 2-METHYLNAPHTHALENE OVER MODIFIED HM CATALYSTS

A series of HM catalysts modified with CeO2 and MgO were prepared by impregnation method. Isopropylation reaction of 2-methylnaphthalene (2-MN) with isopropanol to 2-methyl-6-isopropylnaphthalene (2,6-MIPN) catalyzed by modified HM catalyst was carried out in fixed-bed down-flow reactor. The results showed that the optimal reaction conditions of 2-MN isopropylation were the reaction pressure of 2 MPa, reaction temperature of 200℃, n(2-MN): n(i-PrOH): n(Cyclohexane)=1: 3: 70. Under the optimal conditions and over 20%CeO2/HM catalyst, 2-MN conversion reached 37.7%, 2,6-MIPN selectivity and yield were 83.0% and 28.7%, respectively, after 8 h reaction on stream, and over the HM catalyst modified by CeO2 and MgO, the selectivity of 2,6-MIPN could reach 89.5%. The reason is that CeO2 and MgO can decrease the internal and external acid sites of HM catalysts, reduce the non-shape-selective reaction and improve the selectivity to 2,6-MIPN.