NTA-Fe@PDA/H_(2)O_(2)氧化去除废水中盐酸土霉素

NTA-Fe@PDA/H_(2)O_(2) oxidation for removal of oxytetracycline hydrochloride from wastewater

利用聚多巴胺(PDA)与氮川三乙酸(NTA)接枝并螯合Fe^(3+),形成以PDA为载体、NTA为Fe^(3+)螯合剂的芬顿催化剂NTA-Fe@PDA,采用NTA-Fe@PDA/H_(2)O_(2)芬顿氧化法去除废水中盐酸土霉素(OTC).材料表征结果发现,NTA-Fe@PDA属于典型的介孔结构,Fe元素与有机配体成功螯合,PDA的聚合效果良好.探讨了H_(2)O_(2)投加量、NTA-Fe@PDA投加量和初始pH值对OTC降解的影响.结果表明,在NTA-Fe@PDA浓度为200mg/L,H_(2)O_(2)浓度为5mmol/L,初始pH值为4.85的条件下,反应60min后,20mg/L OTC的降解率达到96.23%.自由基鉴定实验表明,·OH是OTC降解过程中的主要自由基.通过LC-MS分析结果推测了OTC降解的中间产物和可能的降解路径.NTA-Fe@PDA在反应体系中重复利用8次以后,OTC的降解率仍在86.80%以上.NTA-Fe@PDA/H_(2)O_(2)芬顿法为抗生素废水处理提供了一种新思路和技术参考.

In this paper,polydopamine(PDA)grafted with nitrilotriacetic acid(NTA)and Fe^(3+)were chelated to form Fenton catalyst.Advanced oxidation process of NTA-Fe@PDA activated H_(2)O_(2) was used to remove oxytetracyclin hydrochloride(OTC)from wastewater.The material characterization analysis showed that NTA-Fe@PDA was a typical mesoporous structure,Fe successfully chelated with organic ligand,and the polymerization effect of PDA was good.The effects of H_(2)O_(2) dosage,NTA-Fe@PDA dosage and initial pH value on the degradation of OTC were investigated.Experimental results indicated that the degradation rate of 20mg/L OTC reached 96.23%after reaction for 60min,under the conditions of 5mmol/L H_(2)O_(2),200mg/L NTA-Fe@PDA and initial pH 4.85.Free radical quenching experiments confirmed that·OH was the main free radical for OTC degradation.The possible degradation path of OTC was inferred by LC-MS analysis.The degradation rate of OTC was still above 86.80%after NTA-Fe@PDA was reused for 8times.Fenton oxidation process of NTA-Fe@PDA provided a new idea and technical reference for the treatment of antibiotic wastewater.