Document Type : Research article

Authors

1 Associate Professor, Department of Environmental Health Engineering, Faculty of Health, Hamedan University of MedicalSciences, Hamedan, Iran.

2 Associate Professor, Department of Biostatistics and Epidemiology, Faculty of Health, Hamedan University of Medical Sciences, Hamedan, Iran.

3 Assistant Professor, Department of Environmental Health Engineering, Social Determinants of Health Research Center, , Faculty of public Health, Hamadan University of Medical Sciences, Hamadan. Iran.

4 Ph.D, Department of Environmental Health Engineering, Student Research Committee, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran.

5 MSc, Department of Environmental Health Engineering, University of Applied Science and Technology (UAST), Zar Center, Karaj, Iran.

Abstract

Background and objective: Industrialization has led not only to an increase in water demand, but also to an increase in water pollution due to the discharge of polluted industrial wastewaters  with high salt content,  and the organic compounds such as phenol  into the water bodies.
This study aimed to investigate  the efficiency of electrocuagulation and electro-Fenton processes in phenol removal from saline wastewater using Taguchi exprimental design method.
Material and methods: This experimental study was performed in a reactor (1 liter) with synthetic phenolic saline wastewater. In this study for electrocoagulation process, the effects of five operation parameters on phenol removal efficiency including reaction time (20-80 min), electrolyte (1-4%), pH (3-5-7-9), initial phenol concentration (500-1000-1500-250 mg/L) and  current density (4-16 mA/cm2) were investigated in four levels by Taguchi L16 orthogonal array. Also for electro-Fenton process, the effects of six operation parameters on removal efficiency in five levels including  reaction time (20-80 min), electrolyte (0-4%), pH (2-3-4-6-8), initial phenol concentration (250-500-1000-1500-2000), current density ( 0-16mA/cm2) and hydrogen peroxide (50-300mg/L) were evaluated by Taguchi L25 orthogonal array. The concentration of phenol was determined according to the estandard method in spectrophotometric wavelength of 500 nm.
Results: Experimental data showed that the optimum phenol elimination condition in electrocuagulation process was initial phenol concentration of 250 mg/L, pH = 5, electrolyt = 3%, curent density of 8 mA/cm2 and reaction time of 60 min. The most influential factor in removal efficiency was the initial concentration (63.2%), and the lowest effect belonged to the electrolyt (4.2%).
The optimum phenol removal condition for electro-Fenton process was initial concentration of 250 mg/L, pH:3, electrolyt:2%, hydrogen peroxide:150 mg/L, current density of 8 mA/cm2 and 20 mine contact time. The most influential factor in elimination efficiency was the curent density (29.12%), and the lowest influence on response variable belonged to the reaction time (3.08%).
Conclusion: This study showed the electro-Fenton process was effective in the removal of phenolthat can be used as an appropriate process in wastewater treatment.

Keywords

1. Asgari G, Feradmal J, Poormohammadi A, Sadrnourmohamadi M, Akbari S. Taguchi optimization for the removal of high concentrations of phenol from saline wastewater using electro-Fenton process. Desalin Water Treat 2016; 57: 1-8
2. Akbari S, Seid-mohammadi A, Faradmal J, Asgari G. An Investigation of the Performance of Electrochemical Process in Simulated Phenolic Saline Wastewater Treatment. J Sabzevar Univ Med Sci 2015; 5: 870-78. (Persian)
3. Akbari S, Ghanbari F, Moradi M. Bisphenol A degradation in aqueous solutions by electrogenerated ferrous ion activated ozone, hydrogen peroxide and persulfate: applying low current density for oxidation mechanism. Chem Eng J 2016; 294: 298-30.
4. Gholami M, Davoudi M, Naseri S, Mahvi AH, Farzadkia M, Esrafili A et al. Optimization of phenolic compounds removal from wastewater in electrochemical oxidation process using catalytic anodes and cellulosic separator. Journal of research in environmental health 2016; 2(2):101-11. (Persian)
5. Sundarapandiyan S, Chandrasekar R, Ramanaiah B, Krishnan S, Saravanan P. Electrochemical oxidation and reuse of tannery saline wastewater. J hazard mater 2010; 180(1): 197-203
6. Can O. COD removal from fruit-juice production wastewater by electrooxidation electrocoagulation and electro-Fenton processes. Desalin Water Treat 2014; 52(3): 65-73
7. Ghanbari F, Moradi M, Eslami A, Emamjomeh MM. Electrocoagulation/flotation of textile wastewater with simultaneous application of aluminum and iron as anode. Environ Proc 2014; 1(4): 447-57
8. Yusefi M, Ghanbari F,  Zazouli M.A , Ahmadi Moghaddam M, Akbari S. Investigation of the Efficiency of Electro-Fenton and UV/TiO2 Processes for Para-Chlorophenol Removal from Aqueous Solutions. J Health 2017; 7: 600-10. (Persian)
9 . Asgari G, Almasi H, Fardmal J, Ghanbari F, Darai Z, Akbari S. Optimization of Catalytic Ozonation Process for Removal of Reactive Black 5 dye Using Bone Char Ash Modified by Magnesium Oxide and Applying Taguchi Design. J Mazandaran Univ Med Sci 2015; 24: 252-64. (Persian)
10. Seid-Mohammadi A, Asgari Gh, Sammadi M, Ahmadian M, Poormohammadi A. Removal of humic acid from synthetic water using chitosan as coagulant aid in electrocoagulation process for Al and Fe electrodes. Res J Chem Environ 2014; 18: 5-10
11. Rahmani AR, Shabanloo A, Mehralipour J, Fazlzadeh M, Poureshgh Y. Degradation of Phenol in Aqueous Solutions Using Electro-Fenton Process. Res J Environ Sci 2015; 9(7) :332-40
12. Dalvand A, Golami M,Ameri A, Mahmudi NA. Treatment of SyntheticWastewater Containing Reactive Red 198 by Electrocoagulation Process. J Health Environ 2011; 22: 401-11. (Persian)
13. Zhou M, Yu Q, Lei L, Barton G. Electro-Fenton method for the removal of methyl red in an efficient electrochemical system. Sep Purifi Technol 2007; 57(2) :380-7
14. Costa CR, Olivi P. Effect of chloride concentration on the electrochemical treatment of a synthetic tannery wastewater. Electrochim Acta 2009; 54(7): 2046-52
15. Zhou M, Tan Q, Wang Q, Jiao Y, Oturan N, Oturan MA. Degradation of organics in reverse osmosis concentrate by electro-Fenton process. J hazard mater 2012; 215: 287-93
16. Rahmani AR, Rezaeivahidian H, Almasi M, Shabanlo A, Almasi H. A comparative study on the removal of phenol from aqueous solutions by electro–Fenton and electro–persulfate processes using iron electrodes. Res Chem Intermed 2016; 42(2): 1441-50
17. Biglari H, Bazrafshan E. Performance evaluation of electrochemical process using iron and aluminum electrodes in phenol removal from synthetic aqueous environment. Iran J Health Environ. 2013;5(4):445-56
18. Umar M, Aziz HA, Yusoff MS. Trends in the use of Fenton, electro-Fenton and photo-Fenton for the treatment of landfill leachate. Waste Manage 2010; 30(11): 2113-21
19. Atmaca E. Treatment of landfill leachate by using electro-Fenton method. J Hazard Mater 2009; 163(1): 109-14
20. Yavuz Y, Koparal AS, Ogutveren UB. Treatment of petroleum refinery wastewater by electrochemical methods. Desalination 2010; 258(1): 201-5