A Novel Application of XRD Technique for the Characterization of Secondary Pore Structure in Modified Y Zeolites

Abstract

Publisher Summary Attempts have been made to correlate the dealumination of Y-zeolites with the unit cell size and with the secondary pore structure and thereby with increased activity and stability of catalyst. The chapter also reports investigation of the intensity changes of crystalline planes of some hydrothermally dealuminated and acid-extracted zeolites and discusses the reasons for these changes. From the study described in the chapter, it can be observed that the very high intensity of the (111) plane may be due to different co-ordination of Al 3+ in this site. Moreover, the intensity variation of (111) with increasing dealumination (from 40% to 98%) is almost regular. From line broadening, it may be possible to predict the formation of secondary pores. Combined application of X-ray diffraction (XRD), transmission electron microscopy (TEM), and N 2 -adsorption desorption provides the details on the secondary pore structures. More work in this direction is in progress.