助剂和制备方法对V2O5/Al2O3催化性能的影响

Additives and preparation methods influence on catalytic properties of V2O5/Al2O3 catalysts

摘要:

用浸渍法制备了负载型MxOy-V2O5/Al2O3催化剂，同时考察了不同的制备方法对MoO3-V2O5/Al2O3催化剂的性能影响。用BET、H2-TPR、TPD平衡法等考察了催化剂的比表面积、氧化还原性能、表面氧脱附性能，结果表明，添加变价助剂Mo、Fe和Cr氧化物会增加供氧数目，提高α-蒎烯转化率。MoO3-V2O5/Al2O3催化剂表面O2-和O-物种较多，活性也较好，桃金娘烯醛收率较高。MoO3-V2O5/Al2O3催化剂的制备方法影响其催化性能，表面化学改性法制备的催化剂表面具有较多O2-和O-物种，有利于催化剂的活性提高, α-蒎烯的转化率达到88.9%，桃金娘烯醛的收率为79.1%。

Abstract:

Abstract: MxOy-V2O5/Al2O3 catalysts were prepared by the impregnation method，at the same time,in order to investigate the MoO3-V2O5/Al2O3 catalytic performance, the MoO3-V2O5/Al2O3 was prepared by the different methods. The surface area, redox properties and the oxygen desorption behavior of catalysts were characterized by BET,H2-TPR and TPD-MS. The analysis of the used catalysts showed that the MoO3-V2O5/Al2O3 , Fe2O3 -V2O5/Al2O3 and Cr2O3 -V2O5/Al2O3 presented the higher number of surface oxygen and conversion rates of α-pinene, the more O2- and O- species exist on the surface of MoO3-V2O5/Al2O3 catalyst, the O2- and O- species can increase catalytic activity and yield of myrtenal. The different pre paration methods would influence on the catalytic performance of MoO3-V2O5/Al2O3 catalysts, the surface modification method could come into being more O2- and O- species，which is propitious to improve catalytic activity, the conversion rates of α-pinene is 88.9%,the yield of myrtenal is 79.1%.