不同粒径磁铁矿的多羧酸改良光-芬顿体系应用

Application of Magnetite with Different Particle Sizes in Polycarboxylic Acid Modified Heterogeneous Photo-Fenton System

研究利用乙二胺-N,N'-二琥珀酸(EDDS)与强磁性的磁铁矿络合成Fe(Ⅲ)-EDDS配合物,在模拟太阳光下与H_2O_2作用生成大量的羟基自由基,用于降解目标底物双酚A(BPA)。结果表明,pH=7.0,粒径100～300 nm的磁铁矿体系中,磁体矿投加量0.8 g/L,EDDS、H_2O_2的浓度分别为0.5、0.5 mmol/L时,11 h后BPA的降解率为50.33%;pH=7.0,粒径20 nm的磁铁矿体系中,磁铁矿投加量0.8 g/L,EDDS、H_2O_2的浓度分别为1.5、0.5 mmol/L时,反应11 h后,BPA的降解率为58.76%。2个降解体系中,磁铁矿、EDDS和H_2O_2均存在适宜的含量。BPA在中性和碱性条件下均有一定程度降解,说明EDDS的添加在一定程度上克服了传统Fenton法适用pH范围窄的缺陷。

The ethylenediamine-N,N'-disuccinic acid(EDDS)in combination with magnetite to form Fe(Ⅲ)-EDDS complexes interacting with H2O2 under simulated sunlight to generate large amounts of hydroxyl radicals,in order to degrade the target substrate bisphenol A(BPA).The results showed that,when under the conditions of magnetite dosage was 0.8 g/L,concentration of EDDS and H2O2 was 0.5 mmol/L and 0.5 mmol/L respectively in magnetite system with 100~300 nm particle size,the removal efficiency of BPA reached 50.33% at pH 7.0 after 11 h;While in the magnetite system with 20 nm particle size,under the conditions of magnetite dosage was 0.8 g/L,concentration of EDDS and H2O2 was 1.5 mmol/L and 0.5 mmol/L respectively,BPA removal efficiency was 58.76% at pH 7.0 after 11 h degradation.In both degradation systems,the optimum content of magnetite,EDDS,and H2O2 was exist,BPA could be degraded at neutral or alkaline conditions,which indicated that the addition of EDDS could overcome the limit of pH in Fenton application.