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试验表明了HZSM-11沸石催化邻二甲苯脱烷基和异构化反应的适用性。这种为单一酸中心所催化的简单反应可作为模型反应表征沸石的表面酸性。试验结果表明HZSM-11沸石表面上存在着使邻二甲苯脱烷基(以甲苯的选择性表示)和异构化(以对二甲苯的选择性表示)活性的两种酸中心。其中脱烷基活性的酸中心较强,其酸中心数随温度的升高而增多,随沸石硅铝比的增大而减少。具有异构化活性的酸中心数随温度的升高而减少,可以认为在较高反应温度下,它会部分转化为具有脱烷基活性的酸中心。吡啶首先使脱烷基活性中心中毒,由吡啶的吸附量可以分别得到沸石表面总活性中心数、脱烷基活性中心数和异构化活性中心数。
Experiments show that HZSM-11 zeolite catalyst for o-xylene dealkylation and isomerization of the applicability. This simple reaction catalyzed by a single acid site characterizes the surface acidity of the zeolite as a model reaction. The experimental results show that there are two types of acid sites on the surface of HZSM-11 zeolite that deactivate o-xylene (selectivity in toluene) and isomerization (selectivity to p-xylene). Among them, the acid sites of dealkylation activity were stronger, the number of acid sites increased with the increase of temperature, and decreased with the increase of zeolite silica-alumina ratio. The number of acid sites with isomerization activity decreases with increasing temperature, and it is believed that at higher reaction temperatures it will be partially converted to acid sites with dealkylation activity. Pyridine first dealkylation activity center poisoning, pyridine adsorption capacity can be obtained zeolite surface active center number, dealkylation activity center number and isomerization activity center number.