Because of the growing concern over highly contaminated crystal violet (CV) wastewater, an FeGAC/H2O2 process was employed in this research to treat CV-contaminated wastewater. The experimental results indicated that the presence of iron oxide-coated granular activated carbon (FeGAC) greatly improved the oxidative ability of H2O2 for the removal of CV. For instance, the removal efficiencies of H2O2, GAC, FeGAC, GAC/H2O2 and FeGAC/H2O2 processes were 10%, 44%, 40%, 43% and 71%, respectively, at test conditions of pH 3 and 7.4 mM H2O2. FeGAC/H2O2 combined both the advantages of FeGAC and H2O2. FeGAC had a good CV adsorption ability and could effectively catalyze the hydrogen peroxide oxidation reaction. Factors (including pH, FeGAC dosage and H2O2 dosage) affecting the removal of CV by FeGAC/H2O2 were investigated in this research as well. In addition, the reaction intermediates were separated and identified using HPLC-ESI-MS. The N-demethylation step might be the main reaction pathway for the removal of CV. The reaction mechanisms for the process proposed in this research might be useful for future application of this technology to the removal of triphenylmethane (TPM) dyes. (C) 2011 Elsevier B.V. All rights reserved.