生物电Fenton系统氧化降解水体中微囊藻毒素-LR  

Oxidative degradation of microcystin-LR in water by bio-electro-Fenton system

作　　者：周海霞[1] 李杰[1] 曾亚琼 许楠[1] 

机构地区：[1]北京大学深圳研究生院环境与能源学院重金属污染控制与资源化重点实验室,深圳518055

出　　处：《环境工程学报》2016年第9期4783-4788,共6页Chinese Journal of Environmental Engineering

基　　金：国家自然科学基金资助项目(51309005);深圳市科技研发资金资助项目(JCYJ20130329180830371)

摘　　要：建立以Fe@Fe_2O_3/非催化碳毡(NCF)为阴极电极的生物电Fenton(BEF)系统,研究其对微囊藻毒素-LR(MCLR)的去除效果,并对反应机理进行探究。实验采用从培养的铜绿微囊藻中提取得到的MC-LR。结果表明,以80%甲醇作提取剂,采用磁力搅拌技术时,MC-LR的提取效率最高,达到1.066 mg·g-1干藻细胞。BEF系统4 h内能完全降解初始浓度为0.5 mg·L-1的MC-LR。由于MC-LR是极性化合物,BEF系统对MC-LR的吸附很少,主要通过Fenton氧化作用去除。通过液相色谱-质谱联用检测到2种可能的降解产物质荷比m/z 947.8和971.3,推测MC-LR在BEF系统中可能的降解途径主要包括:Mdha上CC—CO键的氧化;酰胺键的水解;Adda上苯环的氧化。The removal of MC-LR in the bio-electro-Fenton （BEF） system with an Fe@ Fe2O3/non-cata- lyzed carbon felt （NCF） cathode was investigated, along with its degradation mechanism. Microcystis aeruginosa was cultivated for the extraction of MC-LR. Results indicate that using 80% methanol as the extractant under magnetic stirring improves the MC-LR extraction, resulting in an efficiency of 1. 066 mg · g-1 of dry algal cells. In the BEF system, an initial concentration of 0.5 mg · L-1 MC-LR is completely removed within 4 h. Due to the high polarity of MC-LR, its removal is mainly due to Fenton oxidation with minor adsorption. Two feasible products with m/z values of 947.8 and 971.3 were detected with liquid chromatography-mass spectrometry. MC- LR should degrade via the following pathways in the BEF system ： oxidation of C =C-C =O in Mdha, hydroly- sis of amido bonds, then oxidation of benzene in Adda.

关 键 词：微囊藻毒素-LR 提取 生物电Fenton 降解产物 LC-MS 

分 类 号：X703[环境科学与工程—环境工程]