Collect. Czech. Chem. Commun. 1992, 57, 710-717

Application of 23Na Nutation NMR to Characterize the Cation Effect in Ion-Exchanged NaY Zeolites

Kuei-Jung Chao and Chiung-Fang Lin

Department of Chemistry, National Tsinghua University, Hsinchu 30043, Taiwan, R.O.C.


The two-dimensional sodium-23 nutation NMR was used to monitor the behavior of sodium ions in the partially alkali, alkali-earth or rare-earth ion exchanged NaY zeolites. The sodium-23 nutation spectra of the hydrated and rehydrated Y zeolites consist of two peaks at 1 and 2ωrf in F1 axis with chemical shifts of 0-10 ppm. For the degree of IA, IIA or RE cation exchange <45%, only one peak at 1ωrf was found. For the degree of cation exchange >45%, the second peak at 2ωrf might be observed. The correlation between the relative intensities and lineshapes of two peaks and the nature and distribution of cations in the supercages and sodalite cages with degree of exchange and heating treatment was studied.