iO2光催化降解水中喹诺酮类抗生素的动力学研究

ntibiotics are a group of emerging organic pollutants which are usually found in various water compartments. Therefore, efficiency of photodegradation of three quinolones in water by TiO2-catalysed UV irradiation was investigated with analyzing TiO2 dosage, initial concentration, the pH value and water quality on the photodegradation of quinolones. The degradation efficiency of quinolones can be obtained above 95% under the optimum conditions of TiO2 dosage 1.0g/L, initial concentration 10mg/L, and pH value 7.0 after 80 minutes of photodegradation. TiO2-catalysed UV photodegradation reaction of three quinolone compounds followed the pseudo-first-order kinetic formula, with reaction rate constants from 0.0445 to 0.0710. The half lifes were 9.76 mins, 12.76 mins, and 15.57 mins for lomefloxacin, ciprofloxacin and norfloxacin respectively, which indicated that the photodegradation efficiency order were norfloxacin>ciprofloxacin>lomefloxacin. The photodegradation efficiency of different quinolone compounds in various sources of water varied greatly, with the order of ultra pure water> river water>tap water for both norfloxacin and ciprofloxacin, while the order of river water> tap water >ultra pure water for lomefloxacin.