Synthesis, characterization and catalytic behaviour of entrapped transition metal complexes into the zeolite Y

Abstract

Zeolites encumbered with transition metal ions are promising heterogeneous catalysts. Knowledge about the location and structure of the metal centers is of paramount importance for the understanding of the catalytic potential of these materials. A series of entrapped transition metal complexes in the nanopores of zeolite-Y of the type [M(EVTCH)2]-Y [where M = Mn(II), Co(II), Ni(II) and Cu(II); ethylvanillin thiophene-2-carboxylic hydrazone (EVTCH)] have been synthesized by Flexible Ligand Method (FLM). These materials have been characterized by various physico-chemical techniques such as ICP-OES, GC-MS, elemental analyses, (FT-IR, 1H- and 13C-NMR and electronic) spectral studies, BET, scanning electron micrographs (SEMs) as well as X-ray diffraction patterns (XRD). The catalytic significance of these materials has been carried out over the liquid-phase hydroxylation of phenol with 30 % H2O2 to give catechol as a major product and hydroquinone as a minor product. © 2012 VBRI Press.