发展了基于五氧化二钒(V2O5)和过氧化氢(H2O2)的新型类Fenton体系,探索了此体系产生羟基(·OH)的机制及降解邻苯二甲酸二乙酯(DEP)的效率;并考察了V2O5投加量、H2O2浓度,以及草酸对DEP降解的影响.结果表明,当V2O5投加量为0.1 g·L-1,H2O2浓度为2.0 mmol·L-1,反应24 h后,对DEP(25 mg·L-1)的降解率可达61.1％,增加或降低V2O5投加量和H2O2浓度均不利于DEP的降解.利用电子顺磁共振技术(Electron Paramagnetic Resonance,EPR)耦合5,5-二甲基-1-吡咯啉氮氧化物(DMPO)为捕获剂对反应体系中的主导自由基进行鉴定,发现·OH是体系降解DEP的主要活性物种,利用苯甲酸作为探针分子实现了·OH的间接定量,并初步推测了V2O5活化H2O2的过程.%In this study,a novel Fenton-like reaction based on V2O5 and H2O2was developed,and the mechanism of hydroxyl radical production as well as the efficiency for diethyl phthalate (DEP) degradation was explored in these processes.Additionally,the effects of V2O5 loading,H2O2 concentration and oxalic acid on DEP degradation in the V2O5/H2O2 system were also examined.The results showed that 61.1％ of 25 mg·L-1 DEP was degraded with 2 mmol·L-1 H2O2 in the presence of 0.1 g·L-1 V2O5 within 24 h,which indicated that V2O5 exhibits an excellent ability to catalyze the decomposition of H2O2 for DEP degradation,while both increasing and decreasing V2O5 loading or H2O2concentration inhibited DEP degradation.Electron paramagnetic resonance (EPR) technique coupled with DMPO as spin-trapping agent was used to identify the dominant reactive species,which indicated that hydroxyl radical was the main free radical for DEP degradation in the V2O5/H2O2 system.Chemical probe method with benzoic acid (BA) was further used to quantify the formation of hydroxyl radical and elucidated mechanism of this process.
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