Fig. 7.
Effect of electrolysis time on COD removal efficiency (peroxi electrocoagulation process; initial COD, 190 mg L−1; hydrogen peroxide, 2 mM L−1; pH, 3.0; HRT,60 min; current density, 20 mA cm−2; initial conductivity, 390 μs cm−1; distance between plates, 20 mm).