The electrochemical oxidation of paper mill wastewater was studied using a dimensionally stable anode of composition Ti/RuPb(40%)Ox. The oxidation process was analyzed as a function of electrolysis time and with respect to the cell potential difference, electrolyte (NaCl) concentration, and pH of the sample. The purification of the effluent was evaluated through measurements of the removal of chemical oxygen demand (COD), color, and total polyphenols, and using UV-Vis spectroscopy. The results showed that the presence of NaCl is a determining factor in the purification process. Electrolysis of wastewater containing 5 g/L NaCl at a cell potential difference of 6 V for 120 min, removed 99% of COD and the percent removal values of color and polyphenols were 95% after 15 min of electrolysis. The UV-Vis spectrum showed evidence of the formation of hypochlorite ions (ClO-) during the electrolysis process, indicating that the electrochemical oxidation proceeds via an indirect mechanism with the participation of hypochlorite ions.
M. Ali and T. R. Sreekrishnan, “Aquatic Toxicity from Pulp and Paper Mill Effluents: A Review,” Advances in Environ-mental Research, Vol. 5, No. 2, 2001, pp. 175- 196. doi:10.1016/S1093-0191(00)00055-1
E. R. Nestmann, “Detection of Genetic Activity in Effluent from Pulp and Paper Mills: Mutagenicity in Saccharomyces Cerevisiae,” In: F. K. Zimmerman, R. E. Ta- ylor-Mayer, Eds., Testing in Environ-mental Pollution Control, Horwood, London, 1985, pp. 105-117.
G. Thompson, J. Swain, M. Kay and C. F. Forster, “The Treatment of Pulp and Paper Mill Effluent: A Review,” Bioresource Technology, Vol. 77, No. 3, 2001, pp. 275- 286. doi:10.1016/S0960-8524(00)00060-2
D. Pok-hrel and T. Viraraghavan, “Treatment of Pulp and Paper Mill Wastewater,” Science of the Total Environment, Vol. 333, No. 1-3, 2004, pp. 37-58. doi:10.1016/j.scitotenv.2004.05.017
M. Belmont, C. Xavier, J. Decap, M. Martinez, P. Sierra-Alvarez and G. Vidal, “Improved Aerobic Biodegradation of a Abietic Acid in ECF Bleached Kraft Mill Effluent due to Biomass Adaptation,” Journal of Hazardous. Material, Vol. 135, No. 1-3, 2006, pp. 256-263. doi:10.1016/j.jhazmat.2005.11.061
P. Malavyva and V. S. Rathore, “Biorremediation of Pulp and Paper Mill Effluent by A Novel Fungal Consortium Isolated From Polluted Soil,” Bioresource Technology, Vol. 98, No. 18, 2007, pp. 3647-3651. doi:10.1016/j.biortech.2006.11.021
I. C. Nair, K. Jaya-chandran and S. Shashidhar, “Treatment of Paper Factory Ef-fluent using a Phenol Degrading Alcaligenes sp under Free and Immobilized Condition,” Bioresource Technology, Vol. 98, No. 3, 2007, pp. 714- 716. doi:10.1016/j.biortech.2006.02.034
A. C. Rodrigues, M. Boroski, N. S. Shimada, J. C. Garcia, J. Nozaki and N. Hioka, “Treatment of Paper Pulp and Paper Mill by Coagula-tion-Flocculation followed by Heterogeneous Photocatalysis,” Journal of Photochemistry and Photobiology A, Vol. 194, No. 1, 2008, pp. 1-10. doi:10.1016/j.jphotochem.2007.07.007
M. R. Assalin, E. S. Almeida and N. Durán, “Combined System of Activated Sludge and Ozonation for the Treatment of Kraft E1 Effluent,” International Journal of Environmental Research and Public Health, Vol. 6, No. 3, 2009, pp. 1145-1154. doi:10.3390/ijerph6031145
M. R. Assalin, M. A. Rosa and N. Durán, “Remediation of Kraft Effluent by Ozonation: Effect of Applied Ozone Concentration and Initial pH,” Ozone: Science & Engineering, Vol. 26, No. 3, 2004, pp. 317-322. doi:10.1080/01919510490456196
M. R. Assalin, E. S. Almeida, M. A. Rosa, S. G. Moraes and N. Durán, “Applica-tion of Ozonization Process in Industrial Wastewaters: Textile, Kraft E1 and Whey Effluents,” Environmental Technology, Vol. 25, No. 8, 200- 4, pp. 867-872. doi:10.1080/09593330.2004.9619379
S. Mahesh, B. Prasad, I. D. Mall and I. M. Mishra, “Electrochemical Degra-dation of Pulp and Paper Mill Wastewater. Part 1. COD and Color Removal,” Industrial & Engineering Chemistry Re-search, Vol. 45, No. 48, 2006, pp. 2830-2839. doi:10.1021/ie0514096
G. Chen, “Electrochemical Technologies in Wastewater Treatment,” Separation and Puri-fication Technology, V- ol. 38, No. 1, 2004, pp. 11- 41. doi:10.1016/j.seppur.2003.10.006
A. P. Buzzini, A. J. Motheo and E. C. Pires, “Assessment of Electrochemical and Chemical Coagulation as Post- treatment for the Effluents of a UASB Reactor Treating Cellulose Pulp Mill Wastewater,” Water Science and Technology, Vol. 52, No. 1-2, 2005, pp. 183-188.
M. U?urlu, M. H. Karao?lu and ?. Kula. “Ex-perimental Investigation of Chemical Oxygen Demand, Lignin and Phenol Removal from Paper Mill Effluents Using Three- Phase Three-Dimensional Electrode Reactor,” Polish Journal of Environmental Studies, Vol. 15, No. 4, 2006, pp. 647-654.
M. Zaied and N. Bellakhal, “Electrocoagulation Treatment of Black Liquor from Paper Industry,” Journal of Hazardous Material, Vol. 163, No. 2-3, 2009, pp. 995- 1000. doi:10.1016/j.jhazmat.2008.07.115
S. Khansorthong and M. Hunsom, “Remediation of Wa- stewater from Pulp and Paper Mill Industry by the Electrochemical Technique,” Chemical Engineering Journal, Vol. 151, No. 1-3, 2009, pp. 228-234. doi:10.1016/j.cej.2009.02.038
H. B. Beer, “The Inven-tion and Industrial Development of Metal Anodes,” Journal of the Electrochemical Society, Vol. 127, No. 8, 1980, pp. 303C-307C. doi:10.1149/1.2130021
S. Trasatti, “Electrocatalysis: Understanding the Success of DSA?,” Electrochimica Acta, Vol. 45, No. 15-16, 2000, pp. 2377-2385. doi:10.1016/S0013-4686(00)00338-8
C. Comninellis and G. P. Vercesi, “Characterization of DSA Type Oxygen Evolv-ing Electrodes: Choice of a Coating,” Journal of Applied Elec-trochemistry, Vol. 21, No. 4, 1991, pp. 335-345. doi:10.1007/BF01020219
APHA (American Public Health Association), “Standard Methods for the Examination of Water and Wastewater,” 20th Edition, APHA, American Water Works Association, and Water Pollution Control Fed-eration, Washington, D.C., 1998.
T. Zayas, V. Rómero, L. Salgado, M. Meraz and U. Morales, “Applicability of Coagula-tion/Flocculation and Electrochemical Processes to the Purifi-cation of Biologically Treated Vinasse Effluent,” Separation and Purification Technology, Vol. 57, No. 2, 2007, pp. 270-276. doi:10.1016/j.seppur.2007.04.019
K. Rajeshwar, J. G. Iba?ez and G. M. Swain, “Electrochemistry and Environment,” Journal of Applied Electrochemistry, Vol. 24, No. 11, 1994, pp. 1077-1091. doi:10.1007/BF00241305
U. B. ??ütv Eren, E. Torüe and S. Koparal, “Removal of Cyanide by Anodic Oxidation for Wastewater Treatment,” Water Research, Vol. 33, No. 8, 1999, pp. 1851- 1856. doi:10.1016/S0043-1354(98)00362-5
D. Rajkumar and K. Palanivelu. “Electrochemical Trea- tment of Industrial Wastewater,” Journal of Hazardous Materials, Vol. 113, No. 1-3, 2004, pp. 123-129. doi:10.1016/j.jhazmat.2004.05.039
Y. Feng, D. W. Smith and J. R. Bolton, “Photolysis of Aqueous Free Chlorine Spe-cies (HOCl and OClˉ) with 254 nm Ultraviolet Light,” Journal of Environmental Engineering and Science, Vol. 6, No. 3, 2007, pp. 277- 284. doi:10.1139/S06-052
D. Rajkumar, B. J. Song and J. G. Kim, “Electrochemical Degradation of Reactive Blue 19 in Chloride Medium for the Treatment of Textile Dyeing Wastewater with Identification of Intermediate Com-pounds,” Dyes and Pigments, Vol. 72, No. 1, 2007, pp. 1-7. doi:10.1016/j.dyepig.2005.07.015
C. R. Costa and P. Olivi, “Effect of Chloride Concentration on the Electrochemi-cal Tretment of Synthetic Tannery Wastewater,” Electro-chimimica Acta, Vol. 54, No. 7, 2009, pp. 2046-2052. doi:10.1016/j.electacta.2008.08.033
M. Gotsi, N. Ka-logerakis, E. Psillakis, P. Samaras and D. Mantzavinos, “Elec-trochemical Oxidation of Olive Oil Mill Wastewaters,” Water Research, Vol. 39, No. 17, 2005, pp. 4177-4187. doi:10.1016/j.watres.2005.07.037
C. J. Israilides, A. G. Vlyssides, V. N. Mourafeti and G. Karvouni, “Olive Oil Wastewater Treatment with the Use of an Electrolysis Sys-tem,” Bioresource Technolology, Vol. 61, No. 2, 1997, pp. 163-170. doi:10.1016/S0960-8524(97)00023-0
U. Tezcan Un, U. Altay, A. S. Koparal and U. B. Ogutveren, “Complete Treatment of Olive Mill Wastewaters by Electrooxidation,” Chemical Engineering Journal, Vol. 139, No. 3, 2008, pp. 445-452. doi:10.1016/j.cej.2007.08.009