Proceedings of the 4 th World Congress on Civil, Structural, and Environmental Engineering (CSEE’19) Rome, Italy – April 7-9, 2019 Paper No. ICEPTP 152 DOI: 10.11159/iceptp19.152 ICEPTP 152-1 Wastewater Treatment by Electrocoagulation: A comparative study using different anode materials Khaled Zaher 1 , Abdelsalam Elawwad 1 , Rana Nadeem 2 1 Environmental Engineering Dept., Faculty of Engineering, Cairo University El-Gamaa St., 12613 Giza, Egypt elawwad@cu.edu.eg, dr.khaledzaher@gmail.com 2 Sanitary and Environmental Engineering Institute, Housing and Building Research Center 87 Tahir St., Dokki, 11511 Giza, Egypt rona.rose@hotmail.com Abstract - This study investigated COD removal by electrocoagulation in both synthetic and real wastewater using different anode material. Experiments were conducted in a batch-scale EC cell using aluminium, iron and copper electrodes as anode and stainless-steel electrode as cathode. Effects of different parameters including pH (4, 7, and 10), time (10 to 60 min), voltage (3 to 12 V) were studied in order to evaluate the efficiency of electrocoagulation process. The initial synthetic COD concentration was 1000 mg/l. The highest COD removal efficiency of 97.7% was observed by aluminium electrode under the following conditions: pH = 7, time of 60 min, and voltage of 12 V. Moreover, it was observed that most of COD removal happened during the first 10 min (about 86%) then the removal rate decreased. For real wastewater, the highest COD removal efficiency was 91.9% which achieved by using aluminium electrode, pH =7.4, time of 60min, and voltage of 12 V. The results showed the feasibility of electrocoagulation process for the treatment of high- strength municipal wastewaters. Keywords: Electrocoagulation, Wastewater treatment, Chemical Oxygen Demand, Anode material. 1. Introduction Wastewater contains high organic and nutrient concentrations. So, direct discharge of raw untreated sewage into the water body is one of the main sources of pollution. The main objectives of wastewater treatment are protecting the environment, conserving fresh water resources and wastewater reuse [1]. Nowadays, more effective methods are required to treat a wide range of pollutants. Electrocoagulation (EC) is a promising process in which a sacrificial metal anode produces electrically active coagulants. EC has many advantages as it is fast, simple and cost-effective method. Moreover, it requires lower maintenance cost and needs less labour [2]. EC involves many chemical and physical phenomena that use consumable metal electrodes to supply ions into the water stream. Electrodes are classified into cathode and anode based on the type of reaction occurred on its surface where, reduction occurs at the cathode, while oxidation occurs at the anode [3]. The amount of electricity that passes through the cell governed the amount of substance that undergoes oxidation or reduction at each electrode [4]. Metal anodes continuously scarifies metal ions, which immediately hydrolyse to polymeric metal hydroxide. Pollutants present in wastewater are treated either by chemical coagulation or by attachment to coagulated particles. They are then removed by electro-flotation, sedimentation, or filtration. The literature indicates that EC can be used to treat water containing pollutants such as: heavy metals, textile wastewater, oily wastewater, food industry, potable water, urban wastewater, oil wastes, Paper Mill Wastewater, and many other pollutants [5-9]. In this study, the authors want to investigate the efficiency of EC process in treating municipal wastewater. EC is a simple technology, needs small footprint and isn’t limited by the existence of toxic compounds or pH. So, it can be used in rural areas which suffer in many countries from lack of appropriate sanitation services [10]. The aim of this study is to compare between different anode electrode materials including Aluminum (Al), Iron (Fe), and Copper (Cu) in EC process used for the removal of chemical oxygen demand (COD) in wastewater.