Study On The Activation And Transformation Of Isobutane Over Acidic Zeolite H-Y

Understanding of the mechanisms in heterogeneously catalyzed reactions is not only of fundamental interest for refinement of theories in modern chemistry, but also of practical importance for optimization of existing industrial processes and development of new ones. Crystalline aluminosilicate zeolites are important heterogeneous catalysts and have been widely utilized in petroleum refining chemistry, such as in cracking, isomerization, and alkylation processes. Aiming to offer new information for the development of zeolite chemistry, especially for the understanding of acid-base catalysis in heterogeneous systems, the activation and transformation of isobutane over acidic zeolite H-Y has been investigated in this thesis.In Chapter I, were introduced first the basic knowledge on molecular sieves, the GC-MS technique, and the utilization of isobutane in petrochemical industry. It was then followed by a survey on mechanistic investigations of isobutane activation over acid zeolites.In Chapter II, the acidic zeolite H-Y was synthesized and further characterized by powder XRD and solid-state NMR techniques. GC-MS analysis was then applied to identify the product distribution for isobutane activation over H-Y zeolite under different conditions (reaction temperature, heating duration, and reactant loading). The reaction mechanism for isobtuane activation and transformation on acidic zeolites was, therefore, proposed and discussed on the basis of experimental data obtained by GC-MS techniques.