制备方法对氧化镁负载的钼钒磷酸铜催化剂结构和催化性能的影响

在乙醇溶液中采用不同的浸渍方法制备了氧化镁负载的钼钒磷酸铜催化剂，利用XRD、IR和BET比表面测定等测试手段对催化剂进行了表征．XRD和IR表征结果表明，负载的钼钒磷酸铜在载体表面均匀分散，而且能够保持Keggin型结构．XRD和BET比表面测定结果说明，经12h浸渍制备的催化剂（H4PMo11VO40-CuO／MgO12H）化学和结构性能发生变化；其它两种方法制备的催化剂（H4PMo11VO40-CuO／MgO和Cu2PMo11VO40／MgO）没有化学和结构性能的变化，而且这两种催化剂具有相近的表征结果，说明两种催化剂具有相似的结构特征，以正己醇氧化脱氢生成正己醛反应评价了催化剂的催化反应性能，结果表明，H4PMo11VO40-CuO／MgO和Cu2PMO11VO40／MgO催化剂显示出比H4PM011VO40-CuO／MgO12H更高的催化反应活性。

The Effect of Different Preparation Methods on the Structure and the Catalytic Properties of MgO Supported Cu2 PMo11 VO40 catalysts

Magnesia supported copper salt of molybdodovanadophoric acid (Cu-2PMo-{11}VO-{40}) catalysts were prepared in the alcohol by different methods, and characterized by X-ray diffraction (XRD), FT-infrared (IR) spectroscopy and BET surface area measurements. The IR spectroscopy and XRD revealed that the supported heteropolyacid salt preserves Keggin type structure. The XRD and BET surface area measurements showed that the long term (12 h) impregnation method (H-4PMo-{11}VO-{40}-CuO/MgO-{12H}) lead to the problem of chemical and textural instability of catalyst, and the quite similar characterization results suggest that the similar structural feature in the two samples (H-4PMo-{11}VO-{40}-CuO/ MgO and Cu-2PMo-{11}VO-{40}/MgO). The H-4PMo-{11}VO-{40}-CuO/MgO and Cu-2PMo-{11}VO-{40}/MgO exhibit higher catalytic activities than H-4PMo-{11}VO-{40}-CuO/ MgO-{12H} catalyst.