Ashraf Mazaheri Tehrani
Rouhullah Dehghani
Hamid Reza Soheil Arezoomand
Hamid Reza Gilaasi
Zahra Tavakoli

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 Fe۲+/H۲ O۲ /O۳ 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 (۵۰۰ mg/L). The maximum percentage of formaldehyde removal was ۷۲.۵% that was observed in molar ratio of ۲.۴ [H۲ O۲ ]/[Fe۲+]. After determining optimum [H۲O۲]/[Fe۲+], 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 ۰.۷ mg/L ozone concentration and in ۲.۴ of molar ratio for [H۲ O۲ ]/[Fe۲+] was ۸۵.۸۴% after ۲۰ minutes. Moreover, the effect of pH and ozone concentration was significant in degradation efficiency (P<۰.۰۵). Generally, the Fe۲+/ H۲ O۲ /O۳ process seems to be a practical and reliable method in treating the industrial wastewater contaminated with high concentrations of formaldehyde.