Virgin (Fe0) and microbially regenerated (Fe2+) iron turning waste for treating chlorinated pesticides in water.
This work investigated the applicability of iron turning waste as filtration media for treating mixture of organochlorine pesticides (OCPs) in water and the ability of non-pathogenic bacterium Shewanella oneidensis to regenerate the exhausted iron turning waste for reuse. In batch experiments, 1.5 × 104 mg/L of iron turning waste efficiently removed (≥85%) five out of six pesticides in 200 mL of water (20 μg/L for each pesticide) in 10 min. Increasing the iron dose from 2.5 × 103 to 1.5 × 104 mg/L enhanced the removal of heptachlor, endosulfan, dieldrin, and endrin by 5.7, 13.2, 23.3, and 39.4%, respectively, whereas lindane and dichlorodiphenyltrichloroethane removal was comparable when using 2.5 × 103 and 1.5 × 104 mg/L of iron. Better pesticide removal (except lindane) was achieved when the initial concentration of each pesticide was higher (20 μg/L versus 1 μg/L) in the solution. Acidic pH favored OCPs (except endosulfan) removal. S. oneidensis efficiently reduced 80 ± 5% of dissolved ferric iron (Fe3+) to ferrous iron (Fe2+) in 72 h. Microbially regenerated Fe2+ iron removed all six OCPs in water efficiently (52-91%) and at similar levels as provided by virgin iron turning (38-100%). Lindane, endosulfan, and dieldrin removal increased 4-fold using S. oneidensis regenerated iron compared to exhausted iron.
['Abbas|Tauqeer|T|', 'Wadhawan|Tanush|T|', 'Khan|Asad|A|', 'McEvoy|John|J|', 'Khan|Eakalak|E|']
D004726:Endosulfan D004784:Environmental Monitoring D006843:Hydrocarbons, Chlorinated D007501:Iron D010575:Pesticides D020592:Shewanella D014867:Water D014874:Water Pollutants, Chemical
Iron turning waste Chlorinated pesticides Microbial regeneration of iron Water treatment