【摘要】 研究了一系列不同锌含量的ZSM-5样品的呲啶吸附红外光谱和芳构化性能。通过对1616cm^-1红外吸收带的定性和半定量处理,找出了样品的Brnsted酸,L₁₆₁₆酸及正庚烷芳构化活性与样品锌含量的关系,比较了不同方法制备的ZnZSM-5的酸性和芳构化活性,用热重分析测定了HZSM-5和含锌ZSM-5的羟基含量。在实验结果的基础上提出了1616cm^-1所表征的活性中心是一个结构基团,它可由ZnO与ZSM-5上的酸性羟基作用形成,也可由交换进ZSM-5的水合锌离子解离形成,它是ZnZSM-5沸石上的芳构化活性中心。更多还原

【Abstract】 The IR spectra of pyridine adsorption and aromatization properties of hydrocarbons over a series of ZSM-5 zeolite samples with various zinc contents have been studied. Through qualitative and semi-quantitative treatments for the IR band at 1616cm^-1, the relationships between Bronsted acidity, L₁₆₁₆ acidity, aromatization activity of n-heptane and the zinc content of the samples were established.The acidities and aromatization properties of zinc containing ZSM-5 samples prepared by different methods were compared. The contents of hydroxyl group on HZSM-5 and ZnZSM-5 were determined by TGA. Based on the experimental results, it is suggested that the active sites characterized by the IR band at 1616cm^-1 may be a group in framework of zeolite which can be formed by the interaction of ZnO wlth Bronsted sites on ZSM-5 samples or by the interaction of Zn（OH）+with zeolite framework. The active sites of aromatization may be provided by zinc on ZnZSM-5 zeolite.更多还原