Fenton法/草酸钠-Fenton法降解典型抗癌药5-氟尿嘧啶

Degradation of anticancer drug 5-fluorouracil by Fenton and oxalic-Fenton process

本文以典型抗癌药5-氟尿嘧啶(5-FU)为对象,研究了Fenton法和草酸钠-Fenton法对5-FU的降解效果与反应动力学.结果表明,在pH值为3,Fe2+浓度为5 mg·L-1,H2O2/Fe2+物质的量之比为2∶1,反应时间为30 min,5-FU的初始浓度为1 mg·L-1时,Fenton法对5-FU的降解率可达87.55%;在pH值为2.5—4,Fe2+浓度为5 mg·L-1,H2O2/Fe2+物质的量之比为2∶1,草酸根浓度为5 mg·L-1的条件下,草酸钠-Fenton法对5-FU降解率可达100%以上,且草酸钠-Fenton法的适用pH值范围(2.5—6)比Fenton法宽(2—4).Fenton法和草酸钠-Fenton法对5-FU的降解有一个快速的初始阶段(前2 min)和相对缓慢的后续阶段,其动力学符合联合一级动力学模型,且草酸钠-Fenton法的降解速率快于Fenton法.

It is urgent and necessary to develop effective methods to remove residual pharmaceuticals in aquatic environment, due to their potential ecological risk. This paper examined the degradation efficiency and reaction kinetics of an anti-cancer drug 5 fluorouracil （5-FU） by Fenton process and oxalic-Fenton process. The results showed that the degradation rate of 5-FU reached Fenton process, under the condition of initial pH of 3, Fe^2＋ dosage of 5mg·L^-1 , H2O2/Fe^2＋ molar ratio of 2：1 and reaction time of 30 min, while the degradation rate of 5-FU reached 1 Fenton process under the condition of pH range of 2.5-4, Fe^2＋ dosage of 5mg·L^-1,H2O2/Fe^2＋ molar ratio of 2：1, oxalic dosage of 5 mg·L^-1 and reaction time of 30 min. The applicable pH range for oxalic-Fenton process （2.5-6） was obviously broader than that for Fenton process （2-4）. The degradation of 5-FU by Fenton process and oxalic-Fenton process both showed an initial rapid phase （0-2 min） and subsequent retarded phase, and the degradation kinetic fitted the combined first- order kinetic model. The removal rate of 5-FU by oxalic-Fenton process is higher than Fenton process.