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An effective electrochemical Cr(VI) removal contained in electroplating industry wastewater and the chemical characterization of the sludge produced / Sarai Velazquez-Pena in Industrial & engineering chemistry research, Vol. 51 N° 17 (Mai 2012) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 51 N° 17 (Mai 2012) . - pp. 5905–5910 Titre : An effective electrochemical Cr(VI) removal contained in electroplating industry wastewater and the chemical characterization of the sludge produced Type de document : texte imprimé Auteurs : Sarai Velazquez-Pena, Auteur ; Carlos Barrera-Díaz, Auteur ; Ivonne Linares-Hernandez, Auteur Année de publication : 2012 Article en page(s) : pp. 5905–5910 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Electrochemical  Electroplating  wastewater Résumé : The goal of this work is to optimize the electrochemical reduction of hexavalent chromium in electroplating wastewater. The pH, electrolyte composition and concentration, and cathode metal were varied and the effect on reduction rate measured. Although all electrochemical systems studied reduced all Cr(VI) in the solutions, there were clear trends in the speed of the reactions. Because the reaction at pH 2 was faster than that at pH 4, acidity is favored. Higher electrolyte concentrations produced faster rates. Copper cathodes were faster than iron ones. Using the optimized conditions of pH 2 and a copper cathode, along with the high electrolyte concentration already present, actual electroplating wastewater was treated. The rate of Cr(VI) reduction was measured as a function of treatment time and was found to be even higher than that of the synthetic solutions. The 180 mg/L of Cr(VI) in the wastewater was completely reduced in about 15 min under optimal conditions. The sludge generated in the process was analyzed for morphology and elemental composition to provide insight into the mechanism of the reduction. The model electrochemical cell is as effective at reducing hexavalent chromium in actual electroplating wastewater as it is on synthetic solutions, so it can be effectively scaled up to industrial applications. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie200968s [article] An effective electrochemical Cr(VI) removal contained in electroplating industry wastewater and the chemical characterization of the sludge produced [texte imprimé] / Sarai Velazquez-Pena, Auteur ; Carlos Barrera-Díaz, Auteur ; Ivonne Linares-Hernandez, Auteur . - 2012 . - pp. 5905–5910. Industrial chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 51 N° 17 (Mai 2012) . - pp. 5905–5910 Mots-clés : Electrochemical  Electroplating  wastewater Résumé : The goal of this work is to optimize the electrochemical reduction of hexavalent chromium in electroplating wastewater. The pH, electrolyte composition and concentration, and cathode metal were varied and the effect on reduction rate measured. Although all electrochemical systems studied reduced all Cr(VI) in the solutions, there were clear trends in the speed of the reactions. Because the reaction at pH 2 was faster than that at pH 4, acidity is favored. Higher electrolyte concentrations produced faster rates. Copper cathodes were faster than iron ones. Using the optimized conditions of pH 2 and a copper cathode, along with the high electrolyte concentration already present, actual electroplating wastewater was treated. The rate of Cr(VI) reduction was measured as a function of treatment time and was found to be even higher than that of the synthetic solutions. The 180 mg/L of Cr(VI) in the wastewater was completely reduced in about 15 min under optimal conditions. The sludge generated in the process was analyzed for morphology and elemental composition to provide insight into the mechanism of the reduction. The model electrochemical cell is as effective at reducing hexavalent chromium in actual electroplating wastewater as it is on synthetic solutions, so it can be effectively scaled up to industrial applications. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie200968s