ZrO_2/Mo-MCM-41中孔分子筛催化2-甲氧基萘乙酰化反应的研究

ZrO_2/Mo-MCM-41 Mesoporous Molecular Sieve asCatalyst for Acetylation of 2-Methoxynaphthalene

在水热条件下制备了Mo-MCM-41中孔分子筛,以Zr(SO4_)_2·4H_2O为锆源,用浸泡和研磨两种方式制得ZrO_2/Mo-MCM-41催化剂。通过XRD、FT-IR、NH3-TPD及N2吸附-脱附技术对合成的材料进行了表征。结果表明:合成的中孔分子筛催化剂具有良好的中孔结构;在通过浸渍的方式制得的ZrO_2/Mo-MCM-41中孔分子筛中,ZrO_2分散于中孔分子筛的孔道内,在Mo-MCM-41分子筛外表面没有发现ZrO_2的结晶体;在通过研磨方式制得的ZrO_2/Mo-MCM-41中孔分子筛,ZrO_2仅存在于Mo-MCM-41分子筛的外表面;Mo原子没有进入分子筛骨架的内部,而是以氧化物的形式存在于分子筛表面。将合成的ZrO_2/Mo-MCM-41用于催化2-甲氧基萘的乙酰化反应,反应结果与SO42-/ZrO_2、HY及HZSM-5相比,以浸泡方式制得的ZrO_2/Mo-MCM-41中孔分子筛表现出良好的催化活性和对目的产物高的选择性。

The mesoporous molecular sieve Mo-MCM-41 was synthesized under hydrothermal conditions.ZrO2/Mo-MCM-41 was prepared by impregnating and grinding using Zr(SO4)2 as the zirconium source. The obtained materials were characterized by XRD, FT-IR, NH3-TPD and N2 adsorption/desorption analysis techniques. The results indicated that ZrO2/Mo-MCM-41 was of better mesoporous structure and that no crystalline ZrO2 phase could be observed on the surface of Mo-MCM-41 prepared by impregnating. However, there was some crystalline ZrO2 on the surface of Mo-MCM-41 prepared by grinding. Mo atom lay on the surface of Mo-MCM-41 in a form of MoO3.ZrO2/Mo-MCM-41 was used the first time as catalyst in acetylation of 2-methoxynaphthalene. The catalytic results were compared with those obtained by using SO42-/ZrO2, HY and HZSM-5 as catalysts. The ZrO2/Mo-MCM-41 prepared by impregnation was found to be of best catalytic activity.