Abstract: Al2O3-ZrO2 composite carriers have been prepared by the alkoxide sol-gel method, and Cs2O / Al2O3-ZrO2 catalysts have been prepared utilizing ultrasonic impregnation. Besides, the effects of the carriers on the crystal phase structures and the morphologies of the catalysts have been investigated employing X-ray diffractions (XRD), scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS). Moreover, the catalytic activity of the catalysts with single and composite carriers of various Al/Zr ratios was thoroughly discussed by means of the reaction of formaldehyde and methyl acetate affording methacrylate. The results show that the catalysts were of favorable crystal shapes after the calcinations at 500 ℃. Meanwhile, the cellular pores of the materials could lead to satisfactory permeability. Furthermore, the loading of Cs was 4.42%, and the catalyst activity reached maximum with the yield of 14.76% when the molar ratio of Al2O3 and ZrO2 was 1:0.25.
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