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采用浸渍法并通过ＫＢＨ４还原制备超细Ｐｄ－Ｂ／ＳｉＯ２非晶态合金催化剂，以硝基苯（ＮＢ）加氢生成苯胺（ＡＮ）为目标反应，考察了上述催化剂的活性和选择性及热稳定性，并与晶态Ｐｄ－Ｂ／ＳｉＯ２和Ｐｄ／ＳｉＯ２催化剂及非负载型Ｐｄ－Ｂ非晶态合金催化剂进行了比较．研究表明，Ｐｄ－Ｂ／ＳｉＯ２非晶态合金在ＮＢ加氢反应的催化活性和选择性方面显著优于晶态Ｐｄ－Ｂ／ＳｉＯ２和Ｐｄ／ＳｉＯ２催化剂，表明所形成的非晶态结构以及类金属Ｂ的修饰有利于ＮＢ的催化加氢；另一方面，Ｐｄ－Ｂ／ＳｉＯ２非晶态合金的催化活性和选择性及热稳定性均优于Ｐｄ－Ｂ非晶态合金，表明引入载体有利于改善Ｐｄ－Ｂ非晶态合金的催化性能．结合ＢＥＴ、ＩＣＰ、ＸＲＤ、ＸＰＳ、氢吸附等表征技术，讨论了超细Ｐｄ－Ｂ／ＳｉＯ２非晶态合金的催化性能与催化剂结构的关系．
The Pd-B / SiO2 amorphous alloy catalysts were prepared by impregnation method and KBH4 reduction. The aniline (AN) was hydrogenated by nitrobenzene (NB) as the target reaction. The activity and selectivity of the above catalysts were investigated. Stability, and compared with crystalline Pd-B / SiO2 and Pd / SiO2 catalysts and unsupported Pd-B amorphous alloy catalysts. The results show that the Pd-B / SiO2 amorphous alloy is significantly better than the crystalline Pd-B / SiO2 and Pd / SiO2 catalysts in the catalytic activity and selectivity of NB hydrogenation reaction, indicating that the amorphous structure and the like On the other hand, the catalytic activity, selectivity and thermal stability of Pd-B / SiO2 amorphous alloy are better than that of Pd-B amorphous alloy, indicating that the introduction of the carrier has Conducive to improving the catalytic properties of Pd-B amorphous alloy. The relationship between the catalytic properties and the catalyst structure of ultrafine Pd-B / SiO2 amorphous alloys was discussed based on the BET, ICP, XRD, XPS and hydrogen adsorption techniques.