Ciprofloxacin (CPX), a fluoroquinolone antibiotic, is found in the bulk effluents emerged from pharmaceutical industries. Its presence in the effluent may lead to toxicity to the aquatic life and antimicrobial resistance. Hence, the oxidative degradation of CPX by classical Fenton's process was investigated for the present study. The maximum CPX and total organic carbon (TOC) removal from the synthetic wastewater (initial CPX concentration = 100 mg L⁻¹) were 70% and 55%, respectively, under the best reaction conditions ([H₂O₂]:[Fe²⁺] = 10, stoichiometric H₂O₂ concentration = 14.2 mM and initial wastewater pH = 3.0). Five major degradation products could be identified by high resolution liquid chromatography–mass spectrometry (HR LC-MS) which could have resulted by the occurrence of decarboxylation, defluorination, hydroxylation and cleavage of the piperazine ring. The time based detection of ferrous and ferric ions in aqueous phase confirmed the CPX degradation by hydroxyl radicals. A pathway has been proposed for CPX degradation by Fenton's process based on the kinetic decay and/or evolution profiles of CPX and intermediates as well as the release of inorganic ions into the aqueous solution. It was indicated from the rapid respirometric test that the wastewater toxicity was lowered after Fenton's treatment.

环丙沙星（CPX）是一种氟喹诺酮类抗生素，存在于制药工业产生的大批流出物中。它在废水中的存在可能导致对水生生物的毒性和对抗菌剂的耐药性。因此，本研究对经典芬顿法对CPX的氧化降解进行了研究。在最佳反应条件（[H ₂ O ₂ ]：[Fe]下，从合成废水（初始CPX浓度= 100 mg L ^-1）中去除的最大CPX和总有机碳（TOC）分别为70％和55％。²⁺ ] = 10，化学计量的H ₂ O ₂浓度= 14.2 mM，初始废水pH = 3.0）。高分辨率液相色谱-质谱（HR LC-MS）可以鉴定出五种主要的降解产物，这可能是由于哌嗪环的脱羧，脱氟，羟基化和裂解而引起的。基于时间的水相中亚铁离子和三价铁离子检测证实了CPX被羟基自由基降解。基于CPX和中间体的动力学衰减和/或演化曲线以及无机离子向水溶液中的释放，已经提出了通过芬顿方法降解CPX的途径。快速呼吸试验表明，芬顿处理后废水毒性降低。