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采用不同手段研究了催化剂反应前后及在Ｈ２Ｏ和Ｎ２介质中再生时催化剂性质和表面原子浓度及其分布的变化。ＢＥＴ结果表明，Ｎ２介质中再生，催化剂的孔径基本没有变化，而Ｈ２Ｏ介质中再生的催化剂孔径明显增大。化学组成分析结果说明，长期运转使用后的催化剂在Ｎ２和Ｈ２Ｏ介质中再生后其活性组分均有少量流失。电子探针的结果表明，结炭后的催化剂活性组分很不均匀，在Ｎ２和Ｈ２Ｏ介质中再生后其分布得到了明显改善，但仍不如新鲜催化剂分布得均匀。ＸＲＤ谱图的结果说明，Ｎ２介质和Ｈ２Ｏ介质再生的催化剂其晶相是完全相同的，由于再生过程使催化剂表面的Ｍｏ和Ｎｉ之间的相互作用增强了，形成了类钼酸镍的新晶相。ＸＰＳ的电子结合能数据和催化剂再生前后Ｍｏ物种的解析拟合结果都表明，Ｎ２介质对催化剂组成结构的恢复比Ｈ２Ｏ介质好。因此，对于工业装置的ＨＤＮ催化剂的再生，推荐采用氮气空气法。
Different methods were used to study the changes of catalyst properties and surface atomic concentrations and their distributions before and after the catalyst reaction and regeneration in H2O and N2 media. The results of BET showed that the pore size of catalyst was almost unchanged after regeneration in N2 medium, while the pore size of catalyst regenerated in H2O medium increased obviously. Chemical composition analysis results show that after long-term use of the catalyst after regeneration in N2 and H2O medium, the active components are a small amount of loss. The results of the electron probe showed that the active components of the catalyst after the carbonization were very heterogeneous. The distribution of the catalyst after the regeneration in N2 and H2O media was obviously improved, but it was still not as uniform as the fresh catalyst. The results of XRD showed that the catalysts regenerated by N2 and H2O had the same crystal phase. The interaction between Mo and Ni on the surface of the catalyst was enhanced by the regeneration process, forming a new crystal of nickel-like molybdate phase. XPS electron binding energy data and analytic fitting results of Mo species before and after regeneration show that the recovery of catalyst composition structure by N2 is better than that of H2O. Therefore, for the regeneration of HDN catalyst for industrial plants, nitrogen air method is recommended.