DMP和DEP在氧化铁多相体系中的光催化降解

Photodegradation of DMP and DEP in Heterogeneous Iron Oxides/Oxalate Systems under UVA and VIS Illumination

应用水热合成法制备了4种自然界常见的氧化铁:纤铁矿、赤铁矿、针铁矿和磁赤铁矿,选取邻苯二甲酸二甲酯(DMP)和邻苯二甲酸二乙酯(DEP)作为目标物,研究了它们在氧化铁体系中,紫外光和可见光下的降解过程。重点探讨草酸、光源和氧化铁对其光解效率的影响机制,并与其它文献报道的光解体系进行比较。结果显示,如没有草酸的协同作用,目标物很难发生光解;草酸能够显著促进目标物的光解效率,当目标物初始浓度为20 mg/L,紫外光条件下,DMP和DEP反应60 min后的最高降解率可达到98%以上,可见光条件下,反应180min后可达到96%以上。研究体系与其它光解体系比较,绿色、经济的特点显著。

4 different iron oxides such as lepidocrocite, goethite, hematite, maghemite were prepared by hydro-thermal synthesis. Dimethyl phthalate （DMP） and diethyl phthalate （DEP） were chosen as targets to explore their photodegradation process in iron oxides systems under UVA and VIS illumination. The influence mechanism of oxalic acid, light source and iron oxides on targets photodegradation were discftssed in detail. The other photodegradation systems were compared. It was found that targets were difficult to degrade unless there was oxalic acid. Oxalic acid can greatly improve the photodegradation efficiency of targets. When initial concentration of targets was 20 mg/L, the maximum degradation rate of DMP and DEP could exceed 98% under UVA after 60 rnin, and exceed 96% under VIS after 180 min. Compared with the other photochemical system, the studied system was cost effective.