الفهرس 
CHAPTER ? : IntroductionOnly 14 pages are availabe for public view
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Abstract
The development of industry leads to the pollution of the aquatic environment with industrial organic pollutants, which can be led to the spread of bio-recalcitrant pollutants in the aquatic environment biological conventional treatment plants. The presence of these pollutants has many negative impacts on human health such as perfluoroalkyl substances, pharmaceuticals, and pesticides. Sulfamethazine (SMZ) is widely used antibiotic for both of human and livestock and it is considered a highly bio-recalcitrant industrial organic pollutant. The processes of electro-Fenton and anodic oxidation have been recognized as promising processes of the advanced oxidation processes (AOPs), for removal of emerging pollutants. In this work, a comparison was made between both processes for electrochemical activation of persulfate (PS) using Boron Diamond-Doped electrodes (EO/BDD-PS) under the same conditions; It was found that (EO/BDD-PS) is more effective and gives better results. The electrochemical oxidation using PS and BDD (EO/BDD-PS) is one of the most promising and effective techniques in the degradation of industrial organic contaminants, since it has the advantage of low chemical consumption and no sludge production, furthermore, it requires less time, does not consume much energy, the electrodes do not corrode during the reaction, and its lifespan is very long. This technique depends on the production of very strong oxidants such as hydroxyl and sulfate radicals that react with persistent pollutants and convert them to CO2, H2O, and other benign end products. The main objective of the study is to develop a (EO/BDD-PS) system for removal industrial organic pollutants; Therefore, BDD electrodes have been employed for the removal of sulfamethazine (SMZ) from water by electrochemical activation of persulfate. A set of experiments with a central composite design (CCD) was conducted to optimize the operating parameters such as persulfate dose, solution pH, and current density by response surface methodology (RSM). The experimental results indicated a rapid degradation of SMZ even at high initial concentrations. For instance, complete degradation of 50 mg L-1 of SMZ was attained after 15 min at the optimum operating conditions (persulfate loading= 0.47 g L-1, pH= 6, and current density = 21 mA cm-2). The oxidation mechanism of EO/BDD-PS process was studied based on the reactive oxidant species (ROS) revealing that both (•OH) and (SO_4^(•-)) contributed to the degradation of SMZ in the EO/BDD-PS system. Furthermore, the oxidation pathway has been proposed by the suspect screening and tandem mass spectrometry analysis. The performance of EO/BDD-PS showed faster SMZ degradation than electro-Fenton and anodic oxidation processes using the same BDD electrochemical reactor under the same conditions. Furthermore, we provided a cost estimation study revealing that a full-scale application of the EO/BDD-PS system for the treatment of similar contaminated water costs about $2.23 m-3.