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NH_3-TPD技术表征固体催化剂的酸性似乎已很成熟,其实不然。如该技术表征HZSM-5沸石时,有作者观察到773K左右的高温脱氨峰,而有些作者则检测不到。诚然,各作者间所用试样及预处理条件等存在差异,但实验装置和实验操作条件不同带来的影响也不可忽视。此外,该技术在用于表征一些新的较复杂的催化剂时,其程脱谱也会呈现出新现象,这些现象有时是不能通过酸性来解释的,这是因为NH_3作为探针分子不仅具有碱性,同时还有还原性和配位性。本文对载镍沸石上NH_3-TPD谱图中出现的某些新峰进行了剖析和归属。
NH_3-TPD technology characterization of the acidity of solid catalyst seems to have been very mature, it is not. When this technique characterizes the HZSM-5 zeolite, one of the authors observed a high temperature deamination peak around 773K, while some authors did not detect it. It is true that there are differences between the samples used by the authors and pretreatment conditions, but the impact of experimental devices and experimental operating conditions can not be ignored. In addition, when this technique is used to characterize some new and more complex catalysts, the desorption spectrum of the new structure will also show a new phenomenon. These phenomena are sometimes not explained by the acidity, because NH 3 as a probe molecule not only has a base Sex, as well as reducing and coordination. In this paper, some new peaks appearing in NH_3-TPD spectra of nickel zeolites were analyzed and assigned.