Electrocoagulation method is carried out to remove methyl orange from synthetic wastewater using iron-iron electrodes as anode and cathode. Effects of several experimental parameters treatment of methyl orange (MO) dye removal such as pH, initial concentration, current density and electrode's distance have been studied. The Taguchi method using L16orthogonal array\documentclass[12pt]{minimal}
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\begin{document}$$L_{16} {\text{orthogonal array }}$$\end{document} experimental design was applied to optimize the experimental operating conditions that varied at four levels, initial pH (4–10), current density (1–4 mA/cm2), electrode distance (0.5–1.5 cm), and initial concentration (25–100 mg/L), while the removal efficiency (%R) was considered as the response variable. The Taguchi method based on the average S/N graph method, in combination with analysis of variance (ANOVA), was applied to determine the significant parameters that affect the dye removal. The optimum conditions for removal of MO were determined to be initial concentration (25 mg/L), electrode distance (0.5 cm), pH (8), and current density (3 mA/cm2). The Acidity pH factor represents the most significant factor affecting on removal of MO. The optimum response variables are 97.19 and 97.24% for observed and predicted values, respectively at 39.7575 S/N ratio. As a result, an excellent removal of methyl orange dye from wastewater was attained depending upon the best parametric conditions that obtained from Taguchi method.