Elsevier

Journal of Molecular Catalysis

Volume 84, Issue 1, 21 September 1993, Pages 67-75
Journal of Molecular Catalysis

Kinetics of heterogeneous decomposition of hydrogen peroxide with some transition metal complexes supported on silica-alumina in aqueous medium

https://doi.org/10.1016/0304-5102(93)80085-9Get rights and content

Abstract

Silica-alumina in the form of diethylamine (deam)-, dimethylamine (dmam)-, ethylamine (eam)-, ammonia (amm)- and aniline (an) -copper(II) complexes as well as deam-cobalt (II) complex have been used as potentially active catalysts for H2O2 decomposition in an aqueous medium. The reaction was first order with respect to the H2O2 concentration and the rate constants (per g of dry silica-alumina) were determined. A coloured compound, a peroxo-metal complex, which formed at the beginning of the reaction in each case, was found to contain the catalytically active species. The activation energy and the change in the entropy of activation increased with the basicity of the ligands in the following order: an < amm < eam < dmam < deam, which is also the probability sequence for the formation of the activated complex. A reaction mechanism was proposed.

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