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应用ＩＲ，ＸＰＳ，ＴＰＲ，ＮＯ和ＣＯ２吸附及脉冲微反等技术研究了氟硅酸铵处理前后γ－Ａｌ２Ｏ３及负载ＮｉＷ催化剂的表面性质，探讨了其改性机理和它对催化剂活性相的影响．结果表明，经氟硅酸铵处理后，γ－Ａｌ２Ｏ３表面的不饱和四面体空位及其四配位Ａｌ３＋上的强碱性羟基均明显减少，改变了γ－Ａｌ２Ｏ３表面的酸碱性和Ｎｉ２＋在γ－Ａｌ２Ｏ３表面的分布，使ＮｉＯ倾向分布于γ－Ａｌ２Ｏ３的八面体空位．过量的氟硅酸铵处理将明显破坏γ－Ａｌ２Ｏ３表面的碱性羟基，导致ＷＯ３和ＮｉＯ的分散度下降，使改性后催化剂的噻吩加氢脱硫性能降低．
The surface properties of γ-Al2O3 and NiW supported catalysts before and after treatment with ammonium fluorosilicate were studied by means of IR, XPS, TPR, NO and CO2 adsorption as well as pulsed micro-inversion techniques. The modification mechanism and its effect on the active phase of the catalyst were also discussed . The results show that the unsaturated tetrahedral vacancies and the strong basic hydroxyl groups on the tetrahedral Al3 + of γ-Al2O3 decrease obviously after the treatment with ammonium fluorosilicate, which changes the acid-base and γ-Al2O3 The distribution of γ-Al2O3 surface makes NiO tend to distribute in the octahedral vacancies of γ-Al2O3. Excessive treatment of ammonium fluosilicate will obviously destroy the basic hydroxyl groups on the surface of γ-Al2O3, resulting in the decrease of dispersity of WO3 and NiO and the decrease of thiophene hydrodesulfurization of the modified catalyst.