1 23 Environmental Science and Pollution Research ISSN 0944-1344 Environ Sci Pollut Res DOI 10.1007/s11356-011-0691-1 Heterocatalytic Fenton oxidation process for the treatment of tannery effluent: kinetic and thermodynamic studies S. Karthikeyan, M. Ezhil Priya, R. Boopathy, M. Velan, A. B. Mandal & G. Sekaran