SiW_（12）／Al_2O_3为前身态的加氢脱氮催化剂研究

SiW_(12)/Al_2O_3 AS PRECURSOR OF HYDRODENITROGENATION CATALYST

本文制备了担载在Ａｌ_２Ｏ_３上的十二钨硅酸（ＳｉＷ_（１２））为前身态的加氢脱氮催化剂。用ＸＲＤ、ＩＲ表征了催化剂的表面结构。结果表明，在Ａｌ_２Ｏ_３载体上，ＳｉＷ_（１２）仍保持着其Ｋｅｇｇｉｎ结构并以高度分散状态存在。负载在Ａｌ_２Ｏ_３上的ＳｉＷ_（１２）三维钨氧多聚缩合阴离子钨物种前身态催化剂经硫化后，其加氢脱氮反应催化活性比一般ＷＯ_３／Ａｌ_２Ｏ_３硫化所得催化剂高得多。这一结果表明，多聚氧化态钨物种有利于转变为硫化态加氢脱氮反应活性钨物种。

In this paper,12-silicotungstic acid(SiW12) supported on Al2O3 as catalyst precursor of hydrodenitrogenation(HDN) was prepared by incipient impregnation method.From IR spectra and XRD patterns it was seen that the SiW(12) are dispersed up to a high degree on the Al2O3 surface and the Keggin structure of the polymeric oxoanion of SiW(12) was kept. When this kind of catalysts with the multi-condensed tungsten heteropoly acid SiW(12) precursor were sulfided,it has a higher HDN activity than that of conventional sulfided WSx/Al2O3 catalysts prepared by metatungstate as a precursor.From these results,it is appeared that multi-condensed oxoanion tungsten species are ready to be converted into HDNactive structure.