铜半胱胺配合物类Fenton催化降解土霉素的研究

Investigation of Fenton-like catalytic degradation of oxytetracycline by copper-cysteamine complex

为有效去除污染水体中的土霉素,采用水浴升温合成法制备了铜半胱胺配合物(Copper-Cysteamine-Iodine,Cu-Cy-I),并通过扫描电子显微镜(Scanning Electron Microscope,SEM)、X射线衍射(X-ray Diffraction,XRD)、X射线光电子能谱(X-ray Photoelectron Spectroscopy,XPS)等方法对其形貌、结构、化学成分进行表征。为了研究Cu-Cy-I对土霉素的降解效果,考察了光照时间、H_(2)O_(2)浓度、溶液pH值、催化剂质量、溶液的初始质量浓度以及光源等因素的影响。结果显示,在100 m L质量浓度为100 mg/L的土霉素中加入20 mg Cu-Cy-I催化剂、0.025 mol/L H_(2)O_(2),置于高压汞灯下,照射100 min后对土霉素的降解率可达99.0%。采用自由基捕获试验探究了Cu-Cy-I/H_(2)O_(2)体系中的活性自由基,发现羟基自由基(Hydroxyl radical,·OH)、超氧自由基(Superoxide radical,·O_(2)^(-))和光生空穴(Photogenerated electrons,h^(+))三者共同作用并促进土霉素的降解。Cu-Cy-I对土霉素具有较高的降解效果,为抗生素废水的治理提供了一种新方法。

The presence of oxytetracycline residue in water poses a significant health risk to humans.Utilizing Fenton-like catalytic degradation technology proves to be an effective method for oxytetracycline removal from water.Copper-cysteamine complexes(Cu-Cy-I)were synthesized using water bath elevated temperature synthesis and characterized for morphology,structure,and chemical composition using Scanning Electron Microscopy(SEM),X-ray Diffractometry(XRD),and X-ray Photoelectron Spectroscopy(XPS).SEM analysis revealed that the synthesized Cu-Cy-I exhibited a predominantly rectangular lamellar structure,varying in size.XRD analysis indicated diffraction peaks at diffraction angles 2θof approximately 10°and 24.05°.XPS analysis confirmed the presence of Cu,I,N,C,Cl,S,and other elements within the Cu-Cy-I material.Four antibiotics,including tetracycline hydrochloride,gentamycin,doxycycline hydrochloride,and oxytetracycline,were screened to select oxytetracycline as the target for degradation experiments.The degradation effect of Cu-Cy-I on oxytetracycline was studied by investigating various parameters such as light exposure time,H_(2)O_(2)concentration,solution pH,catalyst dosage,initial solution concentration,and light source.Additionally,the study aimed to explore the degradation mechanism.Under neutral conditions,the degradation rate of 100 mL of oxytetracycline with an initial concentration of 100 mg/L,20 mg of Cu-Cy-I catalyst,and 0.025 mol/L of H_(2)O_(2)reached 99.0%after irradiation under a high-pressure mercury lamp for 100 minutes.Even after three cycles of use,the degradation effect remained substantial,demonstrating excellent stability.Free radical trapping experiments were employed to identify the active free radicals in the Cu-Cy-I/H_(2)O_(2)system.Results indicated the collaboration of hydroxyl radicals(·OH),superoxide radicals(·O_(2)^(-)),and photogenerated holes(h+)in promoting the degradation of oxytetracycline.The Cu-Cy-I catalyst synthesized in this study exhibited significant efficacy in oxytetracycline degradation,presenting a novel approach for antibiotic wastewater treatment.