首先制备了兼具酸性和催化醇氧化活性的Keggin型杂多酸H4PMo11VO40，为使其可以重复利用，又制备了孔道均匀、比表面积大的介孔二氧化硅作为载体，并将 H4PMo11VO40固载在二氧化硅上作为催化剂，实现了在外加氧气条件下，一锅法催化果糖经脱水和氧化制备2,5-二甲酰基呋喃（2,5-DFF）。对杂多酸及载体进行了一系列表征，通过优化反应过程得到了最佳反应条件：在120℃下，DMSO作为溶剂，催化剂、果糖与DMSO质量比为1∶10∶100，反应时间4h，前1h通入N2，体系生成5-HMF并防止了果糖的直接氧化，后3h通入O2，催化氧化5-HMF生成2,5-DFF，所得2,5-DFF的最高收率为48.4%。催化剂的重复利用实验表明：使用5次后再次负载仍可保持较高的催化活性。%A Kegin structure molybdovanadophosphoric heteropolyacids(PMoV-HPAs)was developed and used as the catalyst for one-pot synthesis of 2,5-diformyfuran(2,5-DFF)from fructose with oxygen as the oxidant under environmentally benign conditions. Mesoporous silica was prepared to be the carrier. The TEM mapping and other characterizations showed that the PMoV-HPAs was successfully supported on mesoporous silica. With DMSO as the solvent,the optimal reaction temperature was 120℃ and the best mass ratio of catalyst/fructose/DMSO was 1∶10∶100. In order to prevent the oxidation of fructose in the initial stage,the first one hour of the reaction was protected by nitrogen under atmospheric pressure,and the acidic site(H)offered by the PMoV-HPAs promoted the dehydration of fructose to 5-hydroxymethylfurfural(5-HMF). During the next three hours,the metallic site(V)catalyzed the aerobic oxidation of 5-HMF to 2,5-DFF under atmospheric pressure of oxygen and finally a maximum yield of 48.4% for 2,5-DFF was achieved. In addition,H4PMo11VO/SiO2 could be reusable after 5 cycles without significant loss of activity,and it can achieve the best activity after impregnated again.
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