بررسی کارایی فرآیند الکتروپرسولفات بهینه شده با پرکسیدهیدروژن در حذف COD فاضلاب بیمارستانی به کمک روش سطح پاسخ

Efficiency of Electro-Persulfate Process Optimized with Hydrogen Peroxide in Removal of Hospital Wastewater COD by Response Surface Methodology   B. Bina[1], Y. Hajizadeh[2], S. Karimi[3], H. Ahmadnia[4], M. Meserghani[5]   Received: 26/09/2017  Sent for Revision: 25/12/2017    Received Revised Manuscript: 05/05/2018              Accepted: 26/05/2018   Background and Objectives: Hospital wastewaters contain persistent substances such as microbial factors, deterjents, halogenated organic compounds, hormones, antibiotics, and radioactive isotopes that are produced by a variety of  research and treatment activities. This study aimed to remove COD (Chemical Oxygen Demand) of hospital wastewater by optimized electro-persulfate process using response surface methodology Materials and Methods: In this laboratory study,  an electrochemichal batch reactor equipped with four iron electrodes connected to a DC power supply was used for eliminating COD of wastewater. The independent variables (current density, initial pH, H2O2 dosage, persulfate dosage) against COD removal as the dependent variable were investigated using 8.0.6 Design Expert software by the response surface method, and the proposed model was analyzed using ANOVA. Results: The optimal operational condition for COD removal with current density of 40 mA/cm2, initial pH of 5.2, persulfate dosage of 31 mg/L, and hydrogen peroxide dosage of 45 mM was 92.6%. High value of coefficient of determination was 92.4 % and low value of coefficient of variation 4.58%. Conclusion: The response surface  method showed that there was an agreement between the predicted values by the model and the results obtained from the experiments. Simultaneous use of two reactives (persulfate/H2O2) increaces the COD removal efficiency. Therefore, it seems that  electro-persulfate oxidation with hydrogen peroxide is an effective method for the the removal of hospital wastewater COD. Designing experiment using response surface methodology can show the best conditions for COD removal through reducing the number of experimental tests. Key words: Electro-persulfate, Hydrogen peroxide, COD, Hospital wastewater, Response surface methodology   Funding: This research was funded by Iran University of Medical Sciences. Conflict of interest: None declared.   How to cite this article: Bina B, Hajizadeh Y, Karimi S, Ahmadnia H, Meserghani M. Efficiency of Electro-Persulfate Process Optimized with Hydrogen Peroxide in Removal of Hospital Wastewater COD by Response Surface Methodology. J Rafsanjan Univ Med Sci 2018; 17 (5): 407-20. [Farsi]       - Prof.,  Dept. of Environmental Health Engineering, School of Health, Isfahan University of Medical Sciences, Isfahan, Iran, ORCID: 0000-0002-1718-6089 [2]- Assistant Prof., Dept. of Environmental Health Engineering, School of Health, Isfahan University of Medical Sciences, Isfahan, Iran, ORCID: 0000-0002-1901-4475 [3]- Expert in Charge of  Dept. of Environmental Health , West of Tehran Health Center, Iran University of Medical Sciences, Tehran, Iran, ORCID: 0000-0001-6521-143X [4]-  Head of West of Tehran  Health Center, Iran University of Medical Sciences, Tehran, Iran, ORCID: 0000-0002-9258-2612 [5]- PhD Student of Environmental Health Engineering, School of Health, Isfahan University of Medical Sciences, Isfahan, Iran, ORCID: 0000-0002-5619-986X (Corresponding Author) Tel: (021) 66023041, Fax: (021) 66001931, E-mail: [email protected]