In situ and ex situ XANES study of nanodispersed Mo species in zeolites used in fine chemistry catalysis

MARIO RENTERÍA AGNÈS TRAVERSE OSCAR A. ANUNZIATA EDUARDO J. LEDE LILIANA PIERELLA FÉLIX G. REQUEJO

JOURNAL OF SYNCHROTRON RADIATION

Año: 2001 vol. 8 p. 631 - 633

0909-0495

Mo K-edge XANES experiments on Mo-containing zeolites at low Mo loading (1 and 2 wt% of Mo on H-ZSM-11, H-BETA and H-ZSM-5 catalysts), active in fine chemistry reactions, were performed ex situ as function of sample calcination temperature in air (in the range 773-973 K) or in situ at 873 and 973K under N2 flow. The results showed a 4-fold oxygen coordination for the incorporated Mo species in the activated (dehydrated) state. Combining these results with additional data evidences an almost total Mo exchange inside the zeolite channels.