SI-29 NMR-STUDY OF ALKALI-EXCHANGED NAY ZEOLITES

[[abstract]]High-resolution solid-state Si-29 NMR has been applied to the study of partially exchanged Li, K, and Cs NaY zeolites. The order of the Si-29 chemical shifts of dehydrated samples is Li, Na-Y < Na-Y < K, Na-Y. The correlation between the Si-29 chemical shift and the Li or K loading on Li, Na-Y or K, Na-Y was rationalized in terms of the interaction between the framework and the cations inside the small cages. Because of the restrictive migration of large Cs+ ions from the supercages to the small cages, the Si-29 chemical shift of Cs, Na-Y was found to be similar to that of Na-Y.[[fileno]]2010323010086[[department]]化學