基于MIL-53(Fe)构建异相UV/H2O2活化体系高效降解水中四氢呋喃
Efficient degradation of tetrahydrofuran in water by constructing heterogeneous H2O2 activation system based on Fe-based MOFs
邢云青 1吴天阳 2黄敏轩 3冀世锋1
作者信息
- 1. 上海海洋大学,海洋生态与环境学院,上海,201306;上海海洋大学,海洋环境监测与评价中心,上海,201306
- 2. 上海海洋大学,海洋生态与环境学院,上海,201306
- 3. 上海海洋大学,海洋生态与环境学院,上海,201306;曼彻斯特大学,英格兰曼彻斯特市,M13 9PL
- 折叠
摘要
为克服均相光-芬顿体系中pH范围窄、H2O2 活化效率低、Fe2+无法循环使用等缺陷,制备了Fe基MOFs材料MIL-53(Fe)以构建异相H2O2 高效活化体系,并通过XRD、XPS以及UV-vis等表征,以探究MIL-53(Fe)/UV/H2O2 体系去除THF的性能及机理等.降解实验结果表明MIL-53(Fe)/UV/H2O2 体系相比于 UV/H2O2,降解效率提升了 2.4倍,其准一阶降解速率常数(0.0487 min-1)是 UV/H2O2 体系(0.0205 min-1)的2.375倍,并在pH≈6.8(原水),H2O2 添加量为20 mmol·L-1,MIL-53(Fe)投加量为0.1 g·L-1时,降解效果最佳,50 min达到了 94.7%;通过LC-MS分析确定了中间产物,提出了可能的THF降解途径,并利用Gaussian软件通过DFT计算作了验证;从OUR、BOD5/COD、AOS(高级氧化态)、COS(碳氧化态)4方面证明了降解前后溶液可生化性由弱到强的提升;结合活性物种淬灭实验、Fe3+、e-蒙蔽实验以及价导带分析提出了潜在的THF降解机理,验证出·OH是THF降解过程中最重要的活性物种,而光生e-是反应速率提升的主要驱动者.
Abstract
To overcome the defects of narrow pH range,low activation efficiency of H2O2 and non-recyclability of Fe2+in homogeneous photo-fenton system,the Fe-based MOFs material MIL-53(Fe)was prepared to construct a heterogeneous and efficient H2O2 activation system,and characterized by XRD,XPS and UV-vis diffuse reflection to investigate the performance and mechanism of THF removal by MIL-53(Fe)/UV/H2O2 system.The degradation experiments results showed that the degradation efficiency of MIL-53(Fe)/UV/H2O2 system was 2.4 times higher than that of UV/H2O2,and its pseudo-first-order degradation rate constant(0.0487 min-1)was 2.375 times higher than that of UV/H2O2 system(0.0205 min-1),the best degradation efficiency was achieved at pH ≈ 6.8(raw water),H2O2 addition of 20 mmol·L-1 and MIL-53(Fe)dosing of 0.1 g·L-1,reaching 94.7%within 50 minutes;the intermediate products were identified by LC-MS analysis and a possible THF degradation pathway was proposed and verified by DFT calculation using Gaussian software;the biodegradability of the solution was improved from weak to strong before and after degradation was demonstrated in four aspects:OUR,BOD5/COD,AOS(Advanced Oxidation State)and COS(Carbon Oxidation State);combined with the active species quenching experiment,blinding experiment of Fe3+,e-and the valence/conduction band analysis,the potential THF degradation mechanism was proposed,which verified that·OH was the most important active species in the THF degradation process,and photogenerated e-was the main driver of the increasment of reaction rate.
关键词
四氢呋喃/MIL-53(Fe)/光催化/可生化性/降解机理Key words
tetrahydrofuran/MIL-53(Fe)/photocatalysis/biodegradability/degradation mechanism引用本文复制引用
出版年
2024
NETL
NSTL
万方数据