en تخصصي Special مقاله اصیل Original Article Background: Electro-oxidation is developed as an electrochemical method to overcome the problems&nbsp;of&nbsp; the conventional &nbsp;decolorization technologies and is an appropriate alternative for the treatment of&nbsp;colored wastewater from various industries. The purpose of this study was to evaluate the efficiency of the electrochemical oxidation process in&nbsp; removal &nbsp;of chemical oxygen demand (COD) and Acid Red 18&nbsp;(AR18) dye from aqueous solutions.<br> Methods: In this research, a laboratory scale of electro-coagulation reactor for the treatment of synthetic&nbsp;wastewater was made and studied. The effects of different variables including pH, current density, dye&nbsp;concentration, and electrolysis time were investigated. The experiment steps were designed by Design-Expert 10 software using the selected variables. Finally, the dye and COD analysis was performed by&nbsp;spectrophotometer. The optimization was performed using Taguchi fractional factorial design during&nbsp;the removal of dye and COD.<br> Results: Maximum removal of dye (89%) and COD (72.2%) were obtained at pH=3, current density=20&nbsp;mA/cm2, initial dye concentration=100 mg/L, and reaction time=45 min. ANOVA test showed a&nbsp;significant relationship between&nbsp; statistical &nbsp;model and test data. Also, the results indicate that the distribution of the residues of the model was normal.<br> Conclusion: By designing experiments through Taguchi method, the removal process will be optimized&nbsp;and by decreasing the number of experiments, the optimal conditions for pollutant removal will be&nbsp;prepared. The results suggest that the Electro-oxidation system is a very suitable technique for the&nbsp;enhancement of wastewater treatment. Electrolysis, Wastewater, Azo compounds, Models, Statistical, Analysis of variance 241 248 http://ehemj.com/browse.php?a_code=A-10-1-134&slc_lang=en&sid=1 Zabihollah Yousefi abdolaziz.gh1982@gmail.com 10031947532846004223 10031947532846004223 No Department of Environmental Health Engineering, School of Public Health, Mazandaran University of Medical Sciences, Sari, Iran Ali Zafarzadeh alizafarzadeh@yahoo.com 10031947532846004224 10031947532846004224 No Environmental Health Research Center, School of Health, Golestan University of Medical Sciences, Gorgan, Iran Abdolaziz Ghezel abdolaziz.gh1982@gmail.com 10031947532846004225 10031947532846004225 Yes Corresponding Author: School of Health and Health Sciences Research Center, Mazandaran University of Medical Sciences, Sari, Iran