IR spectroscopic studies on the surface chemistry of mordenites modified by ceria

Surface chemistry of mordenite-type zeolites modified by various methods wa s investigated. We found that after cerium ion exchange acidic groups were generated in the samples. Treatment with cerium salt resulted in a sample o f modified surface character. Upon such modification the concentration of t erminating silanol groups sitting mainly on the outer surface of zeolite cr ystals decreased substantially; however, this treatment also influenced the nature of acidic OH groups. (C) 2001 Elsevier Science B,V. All rights rese rved.