Optimizing design parameters to treat the hospital wastewater effluent using hybrid sono-Fenton-electrocoagulation processes

Abstract Combining electrochemical (EC) with advanced oxidation processes (AOPs) has shown considerable potential in water and wastewater treatment. The current study looked at treating hospital wastewater using the sono-Fenton-electrocoagulation (SF-EC) method with dual application of (Fe/Fe) electrodes to improve the removal of COD and nitrate. Numerous studies have so far employed various heterogeneous AOPs to remove the COD and nitrate from hospital wastewater (HWW). Nevertheless, the use of SF-EC based integrated procedures was not previously evaluated. It has been investigated how the pH of solution, treatment duration, H 2 O 2 , and current effect the elimination of COD and nitrate. The outcomes were optimized using central composite design (CCD), a special feature of the response surface methodology (RSM). The quadratic model was proposed for SF-EC process optimization. The COD and nitrate reductions were found to have R 2 values of 0.99 and 0.99, respectively, using the quadratic polynomial equation. The findings demonstrated that high removal efficiency 91.2 5 % for COD and 97.48 % for nitrate were obtained at pH of 9, treatment time of 50 min, H 2 O 2 concentration of 20 mg/L and current of 0.7 Amp and the lowest removal efficiency 34.32 % for COD and 38.36 % for nitrate was obtained at pH 3, treatment time 40 min, H 2 O 2 concentration 15 mg/L, and current 0.6 Amp. pH is a crucial factor, alongside H 2 O 2 , treatment time and current that directly affects COD and nitrate phosphate removal. The sono-Fenton-electrocoagulation process is considered a feasible treatment option for hospital wastewater since it has typically yielded positive results.