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本文用Ｈａｍｍｅｔｔ指示剂法和吡啶中毒脉冲色谱法测定了ＺＳＭ－５型分子筛催化 剂的酸度和酸强度分布。选择了ＮＨ４离子最佳交换条件。考察了不同交换度、 ＮＨ４－型催化剂的焙烧温度和焙烧时间对山苯歧化反应性能的影响，并与酸度测定 结果相关联。 试验指出，随着ＮＨ４离子交换度的增加，酸性中心总数及强酸中心都增加， 反应活性不断提高，直至交换平衡。高温焙烧过程中有脱羟基和脱铝作用发生，致使 反应活性下降，对二甲苯选择性提高． 吡啶中毒试验证明了强酸中心有利于生成间二甲苯，弱酸中心有利于选择生成对 二甲苯。
In this paper, the acidity and acid strength of ZSM-5 molecular sieve catalyst were determined by Hammett indicator method and pyridine poisoning pulse chromatography. The NH4 ion was selected as the best exchange condition. The effects of different exchange degrees, calcination temperature and calcination time of NH4-type catalyst on the disproportionation reaction of p-phenylenediamine were investigated. The results were correlated with the results of acidity determination. The experiment indicated that with the increase of ion exchange degree of NH4, the total number of acidic centers and strong acid centers increased, and the reactivity increased continuously until the exchange equilibrium was reached. Dehydroxylation and de-alumination occur during the high-temperature calcination, resulting in the decrease of the reactivity and the increase of para-xylene selectivity. Pyridine poisoning test proved strong acid center is conducive to the generation of meta-xylene, weak acid center is conducive to the choice of generation of para-xylene.