Hardly biodegradable complexes present in water resources could be considered as a problem, a part of which origins from the incomplete treatment of these contaminants in wastewater treatment plants. Organic matters present in pharmaceutical wastewater treatment plants outflow could cause environmental hazards, such as antimicrobial resistance. Hence, in this thesis have been tried to find a method capable of treating pharmaceutical wastewater as completely as possible. The consumed synthetic wastewater is made of equal organic load of four highly used antibiotics in Iran, which are amoxicillin, cephalexin, clindamycin and doxycycline. Chemical Oxygen Demand(COD) is used as the indicator parameter and efficiency of each method is reported by their capability of reducing the wastewater COD. Even though Dissolved Air Flotation(DAF) was effective reducing turbidity, but did not have a large impact on reducing COD, therefore was neglected in the further steps. Response Surface Method(RSM) is used to design the experiments. Optimal-IV and Box-Behnken methods were used to design photo-Fenton and electro-photo-Fenton experiments, respectively. In the optimal condition of pH=6, Time=45min, Ferrous Ion Concentration=0.4mg/L and Hydrogen Peroxide Concentration=9.75g/L the photo-Fenton method treated up to 92 percent of the contamination. In the optimal condition of photo-Fenton and adding electrodes with Time=45min, Electrical Current Density=33.3mA/cm 2 , Electrodes Distance=2cm and with aluminium electrodes, the electro-photo-Fenton method could treat the contamination almost completely and reached 99.34 percent efficiency. Key words : Pharmaceutical Wastewater, Dissolved Air Flotation(DAF), photo-Fenton, electro-photo-Fenton, Response Surface Method
