AHMED, O S and DUTTA , D K
(2005)
FRIEDEL-CRAFTS BENZYLATION OF BENZENE USING ZN AND CD IONS EXCHANGED CLAY COMPOSITES.
J Molecular Catalysis A-CHEMICAL, 229 (1-2).
pp. 227-231.
Abstract
Metal ion-exchanged clay composites such as MII–Mont and MII–Mont (AT) where M=Zn and Cd, Mont=montmorillonite clay of the
typesMont1(SWy-2)andMont2(Neelkanth),andAT=acidtreatedhavebeensynthesized,characterizedandevaluatedascatalystsforFriedelCraftsreactionparticularlyforbenzylationofbenzene.XRDstudyrevealsthat,ingeneral,thebasalspacing(d001)increasesastheinterlayer
cations of Na–Mont or H+–Mont are exchanged with Zn2+ or Cd2+ ions and interlamellar spacings are maintained in the range 3.9–5.3 and
4.3–6.0 ˚A, respectively, at room temperature. The basal spacing (d001) of Mont1 supported composites are higher than Mont2 and therefore
substantiatetheadvantageoftheformeroverthelatterinpreparingmetalion-exchangedclaycompositesusefulassolidacidcatalysts.During
theinitialbenzylationreactions,Cd2+-exchangedcomposites,ingeneral,showhigheractivitybutinthelongrunZn2+-exchangedclaysexhibit
highercatalyticactivities.Ingeneral,acidtreatedmetalion-exchangedclaycompositesexhibithighercatalyticactivitythannon-acidtreated
ones because the former show higher surface area as well as higher acid sites.
© 2004 Elsevier B.V. All rights reserved.
Actions (login required)
|
View Item |