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运用ＢＥＴ、ＸＲＤ、ＦＴ－Ｒａｍａｎ以及微量吸附量热等手段对由浸渍三种晶型氧化锆及其前体氢氧化锆制备的负载钨催化剂的结构及其表面酸性进行了研究。结果表明起始原料和制备条件对氧化锆的结构有显著影响。浸渍在氢氧化锆上的钨物种会使氢氧化锆转变为四方晶型氧化锆。但浸渍于氧化锆上的钨物种使氧化锆发生晶型转变相对较难。负载钨催化剂表面强酸位的形成与载体晶型、表面钨物种ＷＯｘ以及ＷＯｘ与载体氧化锆之间的相互作用有关。催化剂上的强酸位可因残留的Ｎａ＋离子所毒化或阻抑。少量Ｙ３＋离子对表面酸性则无明显影响
The structure and surface acidity of supported tungsten catalysts prepared by impregnating three kinds of zirconia and its precursor zirconium hydroxide were investigated by means of BET, XRD, FT-Raman and trace amount calorimetry. The results show that the starting materials and preparation conditions have a significant effect on the structure of zirconia. Tungsten species impregnated on zirconium hydroxide convert zirconium hydroxide to tetragonal zirconia. However, the tungsten species immersed in zirconia makes transformation of zirconium oxide relatively difficult. The formation of strong acid sites on the surface of supported tungsten catalysts is related to the support crystal form, the surface tungsten species WOx and the interaction between WOx and support zirconia. Strong acid sites on the catalyst can be poisoned or repressed by residual Na + ions. A small amount of Y3 + ion had no obvious effect on the surface acidity