Robust Mg(Ca)Zr-Doped Acid-Base Bifunctional Mesoporous Silica and Their Applications in the
Menglu Cai1, Xiaozhong Wang1,2, Yangyang Fang1
1College of Chemical and Biological Engineering, Zhejiang University, Zhejiang Provincial Key Laboratory of Advanced Chemical Engineering Manufacture Technology, Hangzhou 310027, China.
Abstract:
A series of Mg(Ca)Zr-doped acid-base bifunctional mesoporous silica were synthesized to study the impact of the one-step or two-step impregnation method on material structure. The two-step method seems to be a better way to synthesize metal-based functionalized catalyst and their catalytic performance is investigated using deacetalization-Knoevenagel reaction as the probe reaction. The coexisting dual active sites and suitable designing routes endowed highly efficient (Conv. >99.6%, Sel. >99.8%) and robust stability (10 consecutive cycles) of these materials. The present process succeeded in preparing catalysts decorated with acid-base sites by doping acidic and alkali metal species rather than grafting organic groups.
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