Several types of mixed molybdenum and tungsten oxide—SiO₂ materials were prepared using sol–gel and wet impregnation method. In all cases, four different loading of MoO₃ or WO₃ (1, 10, 25 and 40 wt%) were prepared. Materials were characterized using X-ray diffraction, X-ray fluorescence spectroscopy and its acidity was determined by temperature programmed desorption of pyridine. Catalytic activity of these materials was tested in three model reactions providing valuable fine chemicals—aldol condensation, acetalization and esterification. These reactions are usually catalyzed by homogenous catalysts. With increasing interest in environmental protection these catalysts are replaced by heterogeneous ones—offering easy separation from reaction mixture and a possibility of catalyst reuse. More specifically the chosen reactions were: aldol condensation of benzaldehyde with heptanal giving jasmine aldehyde (1), acetalization of heptanal by ethylene glycol giving 2-hexyl-1,3-dioxolane (2) and esterification of lauric acid by methanol giving methyllaurate (3). The prepared materials proved to be catalytically active in above mentioned reactions—in aldol condensation was the best result (78% heptanal conversion, 58% selectivity to jasmine aldehyde, 24 h) obtained using Mo 40 material prepared by impregnation. This material showed to be the best together with W 40 material prepared by sol–gel process in esterification (91 or 94% conversion, 24 h). Acetalization occurs very willingly, best results (heptanal conversion > 90% and selectivity > 90%, 5 h) was obtained using Mo and W 25 and 40 prepared by sol–gel and impregnation process.

使用溶胶-凝胶法和湿法浸渍法制备了几种类型的钼和氧化钨-SiO ₂混合材料。在所有情况下，MoO ₃或WO _3的四种不同负载量制备（1、10、25和40重量％）。使用X射线衍射，X射线荧光光谱对材料进行表征，并通过程序编程的吡啶脱附确定其酸度。这些材料的催化活性在三个模型反应中进行了测试，这些反应可提供有价值的精细化学品-醛醇缩合，缩醛化和酯化。这些反应通常由均相催化剂催化。随着人们对环境保护的兴趣日益增加，这些催化剂被异质催化剂替代-提供了从反应混合物中轻松分离的可能性，并有可能再次使用催化剂。更具体地，选择的反应是：苯甲醛与庚醛的醛醇缩合，得到茉莉醛（1），庚烷被乙二醇缩醛化，得到2-己基-1，3-二氧戊环（2）和月桂酸被甲醇酯化，得到月桂酸甲酯（3）。所制备的材料证明在上述反应中具有催化活性-在醛醇缩合中，使用通过浸渍制备的Mo 40材料可获得的最佳结果（78％的庚醛转化率，58％的茉莉醛选择性（24小时））获得。这种材料与通过溶胶-凝胶法在酯化（91或94％的转化率，24小时）中制备的W 40材料一起表现出最好的性能。使用溶胶-凝胶法和浸渍法制备的Mo和W 25和40可以很容易地发生乙酰化作用，获得最佳结果（庚醛转化率> 90％，选择性> 90％，5 h）。使用通过浸渍制备的Mo 40材料，对茉莉醛具有58％的选择性（24小时）。与通过溶胶-凝胶法在酯化反应中制备的W 40材料（91或94％的转化率，24小时）一起显示出最好的材料。使用溶胶-凝胶法和浸渍法制备的Mo和W 25和40可以很容易地发生乙酰化作用，获得最佳结果（庚醛转化率> 90％，选择性> 90％，5 h）。使用通过浸渍制备的Mo 40材料，对茉莉醛具有58％的选择性（24小时）。与通过溶胶-凝胶法在酯化反应中制备的W 40材料（91或94％的转化率，24小时）一起显示出最好的材料。使用溶胶-凝胶法和浸渍法制备的Mo和W 25和40可以很容易地发生乙酰化，获得最佳结果（庚醛转化率> 90％，选择性> 90％，5 h）。