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研究了在Ｚｎ、Ｐｔ、Ｚｎ－Ｐｔ（双金属）改性的ＺＳＭ－５分子筛上进行的丙烷芳构化反应，并考察了预还原和反应温度对催化丙烷芳构化的影响．结果表明，在ＨＺＳＭ－５上，低温时主要是发生酸性裂解反应；高温则发生氢转移反应生成芳烃．使用Ｚｎ、Ｐｔ、Ｚｎ－Ｐｔ改性的ＺＳＭ－５催化剂显著提高了丙烷转化率和芳烃选择性，这主要是由于丙烷直接脱氢及中间产物脱氢的活性增强所致．氢气的预还原改善了Ｐｔ－Ｚｎ双金属催化剂的脱氢中心，致使中间产物更易于脱氢环化生成芳烃．根据ＴＰＲ结果初步推断，Ｐｔ和Ｚｎ之间存在相互作用，很可能形成了“合金”
The propane aromatization reaction on ZSM-5 zeolites modified with Zn, Pt, Zn-Pt (bimetallic) was studied. The effects of pre-reduction and reaction temperature on the propane aromatization were investigated. The results showed that at low temperature HZSM-5 mainly acidic cracking reaction occurs; hydrogen transfer reaction occurs at high temperature aromatic hydrocarbons. ZSM-5 catalysts modified with Zn, Pt and Zn-Pt significantly improve propane conversion and aromatics selectivity due to enhanced direct dehydrogenation of propane and dehydrogenation of intermediates. Pre-reduction of hydrogen improves the dehydrogenation center of the Pt-Zn bimetallic catalyst, rendering the intermediate product more easily dehydrocyclized to aromatics. Based on the TPR results, it is preliminarily concluded that there is an interaction between Pt and Zn, which is likely to form an “alloy”