采用浓盐酸、浓硝酸、浓硫酸、冰乙酸酸化和乙醚萃取的方法，分别合成了硅钨杂多酸，并用FT-IR、XRD、SEM、TG等对硅钨杂多酸催化剂的结构、热稳定性、表面酸种类等进行了表征。同时以α-蒎烯的异构化反应为探针考察α-蒎烯的转化率和异构化产物的分布。结果表明，不同酸酸化制备的硅钨杂多酸均为典型的Keggin结构，其中硝酸酸化的硅钨杂多酸颗粒大小均匀，稳定性较好，表面同时存在L酸和B酸中心，在α-蒎烯的异构化反应中表现出较好活性和选择性。%The concentrated hydrochloric acid, concentrated nitric acid, concentrated sulfuric acid and ice acetic acid acidiifcation method incorporated with an ether extraction technique was used to prepare silicotungstic heteropoly acid catalyst separately in this study. And FT-IR, XRD, SEM, TG was used to characterize the construction, thermostability, the surface acid species of the silicotungstic heteropoly acid catalyst. Meanwhile theα-pinene isomerization reaction was chosen to investigate the percent conversion ofα-pinene and the distribution of isomerization reaction. Results showed that silicotungstic heteropoly acid catalyst which was prepared by using different acid acidiifcation were typical Keggin structure, among which silicotungstic heteropoly acid catalyst which was prepared by the nitric acid acidiifcation method had homogeneous particle size distribution, better stability and there were L acid and B acid on the surface at the same time what’s more showed higher activity selectivity towardsα-pinene isomerisation.
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