Degradation of Methylene Blue by [RuIII(hedtra)(H2O)]/H2O2 Catalytic System

The [RuIII(hedtra)(H2O)] (hedtra3- = N-hydroxyethylethylenediaminetriacetate) mediated oxidative degradation of methylene blue (MB) in the presence of H2O2 has been achieved under ambient conditions. Based on the results of spectral studies a catalytic pathway involving activation of the dye, MB through its coordination to the ruthenium centre of Ru(hedtra) complex has been suggested. The catalytic-active intermediate [RuIII(hedtra)(OOH)]- was also found to be operative at high H2O2 concentration in effecting MB degradation under the specified conditions. Results of the catalytic studies have been discussed with reference to the data reported for the corresponding Ru(edta) (edta4- = ethylenediamineteraacetate) complex.