Ashraf Mazaheri Tehrani
1, Rouhullah Dehghani
2, Hamid Reza Soheil Arezoomand
1, Hamid Reza Gilaasi
3, Zahra Tavakoli
4* 
1 Department of Environmental Health Engineering, School of Health, Hamadan University of Medical Sciences, Hamadan, Iran
2 Social Determinants of Health Research Center and Department of Environmental Health, Kashan University of Medical Sciences, Kashan, Iran
3 Department of Biostatistics and Epidemiology, School of Health, Kashan University of Medical Sciences, Kashan, Iran
4 Department of Environmental Health Engineering, School of Health, Kashan University of Medical Sciences, Kashan, Iran
Abstract
Formaldehyde is used in many industries for its different chemical characteristics. The wastewater in these industries contains large amounts of formaldehyde which is dangerous and toxic for human and environment. The purpose of this study was to investigate the efficiency of Fe2+/H2 O2 /O3 process in degradation of formaldehyde from synthetic wastewater. This experimental bench-scale study in batch system was conducted on the synthetic wastewater in primary concentration of formaldehyde (500 mg/L). The maximum percentage of formaldehyde removal was 72.5% that was observed in molar ratio of 2.4 [H2 O2 ]/[Fe2+]. After determining optimum [H2O2]/[Fe2+], the effects of pH variables, function time, and ozone concentration were studied in formaldehyde removal. In this process, the maximum degradation efficiency of formaldehyde in 0.7 mg/L ozone concentration and in 2.4 of molar ratio for [H2 O2 ]/[Fe2+] was 85.84% after 20 minutes. Moreover, the effect of pH and ozone concentration was significant in degradation efficiency (P<0.05). Generally, the Fe2+/ H2 O2 /O3 process seems to be a practical and reliable method in treating the industrial wastewater contaminated with high concentrations of formaldehyde.