Vol. 11 No. 2 (2012): Mapana Journal of Sciences
Research Articles

Catalyic Activity of Ruthenium(III) and Palladium(II) Complexes of 2-Methylbenzimidazole (Mebzlh) Encapsulated in Zeolite-Y and ZSM-5 for Liquid Phase Hydroxylation of Phenol

  • B P Nethravathi,
  • K N Mahendra
B P Nethravathi
Department of Chemistry, Christ University, Bangalore 560029, INDIA.
K N Mahendra
Department of Studies in Chemistry, Bangalore University, Bangalore 560001, INDIA.
DOI: https://doi.org/10.12723/mjs.21.2

Published 2021-08-27

Keywords

  • Encapsulation,
  • zeolite-Y,
  • ZSM-5,
  • hydrogen peroxide decomposition,
  • oxidation of phenol

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Abstract

Ruthenium(III) and palladium(II) complexes of 2-methylbenzimidazole (Mebzlh) ligand encapsulated in the super cages of zeolite-Y and ZSM-5 have been synthesized and characterized by various physico-chemical measurements. A suitable reaction condition has been optimized for [Ru(Mebzlh)]-Y by considering the effect of various parameters such as different solvents, concentration of substrate, reaction time and amount of oxidant etc., for the maximum conversion of phenol to a mixture of catechol and hydroquinone. The results obtained showed that selectivity for the catechol formation is ca. 85%, even though the conversion of phenol varies in the order [Ru(Mebzlh)]-Y (35%) > [Pd(Mebzlh)]-Y (15 %) > [Ru(Mebzlh)]- ZSM-5(10 %) > [Pd(Mebzlh)]- ZSM-5 (2 %) after 6 h of reaction time.

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