Abstract - Bell - 9713143 Profs. Alexis T. Bell and Jeffrey A. Reimer will study the catalytic, structural and stability properties of transition-metal cation-exchanged zeolites. Test reactions will include N2O decomposition and olefin dimerization. The physico-chemical probes will involve TPD, and infrared, Raman, NMR, ESR, and UV-Vis spectroscopy, both ex situ and in situ, in order to determine cation distribution and oxidation state before and after reaction, and adsorbed and reactive intermediates identity during reaction. Other techniques such as XRD and SEM for microstructure, and Guoy balance for magnetic susceptibility, will also be used. Double resonance, line broadening, and magic-angle spinning NMR techniques will be exploited to probe the distribution and electronic properties of exchanged cations. The influence of zeolite structure, Si/Al ratio, co-exchanged cations, cation loading, and synthesis and reaction conditions, on catalytic, structural, and stability properties will be determined. In particular, the study will involve the use of commercial ZMS-5 with Si/Al ratios above 10, cation-exchanged with, e.g., Cu, Co, Ag, Ga, In, and Zn. The synthesis-structure-property-performance relations will be studied to provide a basis for the design and industrial application of transition-metal cation-exchanged zeolites. This type of catalysts is of relevance in the petroleum, bulk chemical, fine chemical and environmental protection industries.
