title: Degradation of crystal violet by an FeGAC/H2O2 process.
abstract: Because of the growing concern over highly contaminated crystal violet (CV) wastewater, an FeGAC/H(2)O(2) 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 H(2)O(2) for the removal of CV. For instance, the removal efficiencies of H(2)O(2), GAC, FeGAC, GAC/H(2)O(2) and FeGAC/H(2)O(2) processes were 10%, 44%, 40%, 43% and 71%, respectively, at test conditions of pH 3 and 7.4mM H(2)O(2). FeGAC/H(2)O(2) combined both the advantages of FeGAC and H(2)O(2). FeGAC had a good CV adsorption ability and could effectively catalyze the hydrogen peroxide oxidation reaction. Factors (including pH, FeGAC dosage and H(2)O(2) dosage) affecting the removal of CV by FeGAC/H(2)O(2) 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.
authors.affiliation: Department of Science Application and Dissemination, National Taichung University, of Education, Taichung, Taiwan, ROC.
authors.forename: Chiing-Chang
authors.initials: CC
authors.lastname: Chen
authors.forename: Wen-Ching
authors.initials: WC
authors.lastname: Chen
authors.forename: Mei-Rung
authors.initials: MR
authors.lastname: Chiou
authors.forename: Sheng-Wei
authors.initials: SW
authors.lastname: Chen
authors.forename: Yao Yin
authors.initials: YY
authors.lastname: Chen
authors.forename: Huan-Jung
authors.initials: HJ
authors.lastname: Fan
mesh_terms: D000327:Adsorption; D002384:Catalysis; D002606:Charcoal / Q000737:chemistry*; D002851:Chromatography, High Pressure Liquid; D005296:Ferrous Compounds / Q000737:chemistry*; D005840:Gentian Violet / Q000737:chemistry / Q000302:isolation & purification*; D006861:Hydrogen Peroxide / Q000737:chemistry*; D008855:Microscopy, Electron, Scanning; D015394:Molecular Structure; D010084:Oxidation-Reduction; D021241:Spectrometry, Mass, Electrospray Ionization; D013499:Surface Properties; D014874:Water Pollutants, Chemical / Q000737:chemistry / Q000302:isolation & purification*; D018508:Water Purification / Q000379:methods*
chemical_list: D005296:Ferrous Compounds; D014874:Water Pollutants, Chemical; D002606:Charcoal; D006861:Hydrogen Peroxide; D005840:Gentian Violet