Degradation of Antibiotic Ciprofloxacin Hydrochloride by Photo-Fenton Oxidation Process

The present study investigated the feasibility of using a photo-Fenton oxidation process for the degradation of ciprofloxacin hydrochloride. The pH value of solutions, dosages of hydrogen peroxide and ferrous ion, reaction temperature, and the presence of chloride ion, which affect the degradation of ciprofloxacin hydrochloride wastewater, were studied based on the changes of ciprofloxacin hydrochloride concentration and UV-absorbance of the wastewater. Results indicated that ciprofloxacin hydrochloride could be degraded effectively by photo-Fenton oxidation process in a wide pH range of 3.0 to 5.0; the optimum dosages of hydrogen peroxide and ferrous ion were selected as 5.0 and 0.05 mmol L(-1), respectively; the increase of reaction temperature had a positive effect, but the presence of chloride ion had an inhibitory one on the degradation of ciprofloxacin hydrochloride. Under optimum conditions of C(0) = 15mgL(-1), [H(2)O(2)] 5.0 mmol L(-1), [Fe(2+)] = 0.05mmol L(-1), pH 4.0 and 25 degrees C, no ciprofloxacin hydrochloride was detected in the 45-min reaction time. Degradation kinetics of ciprofloxacin hydrochloride by a photo-Fenton oxidation process follows the first-order reaction kinetics model. The photo-Fenton oxidation process was more rapid and effective for the degradation of ciprofloxacin hydrochloride than conventional Fenton process. It is feasible to employ the photo-Fenton oxidation process to treat ciprofloxacin hydrochloride wastewater; the process also provides an effective approach for other antibiotics wastewater treatment.