稀土掺杂对负载型硅钨杂多酸催化性能的影响

Effect of Rare Earth Ions Doping on the Supported Silicotungstic Acid Catalytic Performance

以碳纳米管为载体负载不同稀土离子掺杂的硅钨杂多酸,采用FT-IR、XRD、SEM、TG等分别对掺杂了La^(3+)、Ce^(4+)、Nd^(3+)、Pr^(3+)的负载型硅钨杂多酸的结构、形貌、热稳定性、酸种类和吸附性能进行了表征。结果表明,掺杂稀土离子的负载型硅钨杂多酸保持了Keggin结构,表面同时具有B酸和L酸酸性中心,以B酸为主。α-蒎烯在催化剂表面发生解离吸附,异构化反应的主要产物是α-松油烯、蒈烯、异松油烯和莰烯等,其中掺杂Pr^(3+)的负载型杂多酸(SiWPr-0.2)有利于α-松油烯的生成,产物中α-松油烯的质量分数为65.10%。

FT - IR, XRD, SEM, TG and micro reactor chromatography device are used to characterize Supported silicotungstic acid doped with rare earth ions on the carbon nanotubes, the loaded type silicon tungsten heteropoly acid structure, morphology, thermal stability, acid type and adsorption performance. The results show that the supported silicon tungsten heteropoly acid doped with rare earth ions keeps the Keggin structure, with B acid and L acid center on the surface, but mainly B acid; the dissociative absorption of a - pinene occurs at the surface of the catalyst; a - terpinene, carene, terpinolene and camphene are the major products of the isomerization reaction; heteropoly acid （SiWPr -0.2） doped with Pr3 ＋ is conducive to the formation of a - terpinene, whose content is 65.10% .