Investigation of using Fenton oxidation process for ampicillin and ciprofloxacin removal from hospital wastewater

Antibiotics are one of the most important pollutants of the aqueous environments. In this study, the efficiency of Fenton advanced oxidation process to remove the antibiotics (ciprofloxacin and ampicillin) was investigated.
This study was performed discontinuously in laboratory scale on the wastewater of one a military hospital. The values of chemical oxygen demand (COD), biochemical oxygen demand (BOD) of wastewater, mixed liquor suspended solids (MLSS), and mixed liquor volatile suspended solids (MLVSS) were measured in summer, winter and spring. Also, efficiency of activated sludge process and Fenton oxidation for removal of BOD, COD, ciprofloxacin, and ampicillin was investigated. Effects of changes of pH, hydrogen peroxide and Fe (II) in efficiency of antibiotics removal in Fenton process were evaluated.
The results showed that the input COD of the wastewater had similar values in the winter and summer. The maximum and minimum concentration of BOD was in late winter and early spring, respectively. The maximum efficiency for elimination of ampicillin antibiotic with 66% was achieved by activated sludge process in early spring. Removal efficacy for ciprofloxacin antibiotics was partially equal to ampicillin. The efficacy of Fenton process for ciprofloxacin and ampicillin removal was 82% and 80%, respectively. The optimum conditions for all parameters were determined. In the Fenton process, the optimum pH was 3.5, Fe (II) and hydrogen peroxide concentrations were 0.7 and 0.45 mmol/L respectively, and retention time was determined one hour. The optimum ratio of H2O2 / Fe (II) was obtained 0.64.
The results of this study showed that the Fenton process is a suitable process for removal of ciprofloxacin and ampicillin antibiotics from wastewater.