改性蛭石负载纳米Fe_(3)O_(4)增强类Fenton降解水中苯酚研究  

Modified vermiculite supported nano-Fe_(3)O_(4)enhanced Fenton-like degradation of phenol in water

作　　者：王兰 祁乙浩 WANG Lan;QI Yihao(School of Environmental Science and Engineering,Shaanxi University of Science&Technology,Xi’an 710000,China)

机构地区：[1]陕西科技大学环境科学与工程学院,西安710000

出　　处：《安全与环境学报》2023年第8期2866-2874,共9页Journal of Safety and Environment

基　　金：国家自然科学基金项目(22076114);陕西省重点研发计划项目(2021SF-452)。

摘　　要：为了提高纳米Fe_(3)O_(4)/H_(2)O_(2)类Fenton降解水中苯酚的效率,以酸化蛭石得到的SiO2纳米片为载体,采用溶剂热法制备了改性蛭石负载纳米Fe_(3)O_(4)复合材料(Fe_(3)O_(4)-改性蛭石)。运用XRD、BET、XPS等对活化剂进行表征,并考察了试验参数降解水中苯酚的影响。结果表明,当Fe_(3)O_(4)-改性蛭石的质量浓度为0.2 g/L,溶液pH值为4,H_(2)O_(2)的投加量为5 mmol/L时,20 min后该活化剂对50 mg/L的苯酚降解率达到100%,且可利用磁分离对活化剂进行有效回收。改性蛭石纳米片的引入有效改善了纳米Fe_(3)O_(4)的团聚现象,提高了活化剂中Fe^(2+)/Fe^(3+)的比例,增大了其比表面积,进而增强了Fe_(3)O_(4)的类Fenton氧化性能。羟基自由基猝灭试验证明,该反应体系中降解苯酚的主要活性物种是活化剂表面结合的羟基自由基。Fe_(3)O_(4)-改性蛭石重复利用3次后仍对苯酚具有较好的降解性能,具有更好的稳定性,成本更低廉。因此,该活化剂有望在含酚废水的实际处理中得到应用。To improve the efficiency of nano-Fe_(3)O_(4)/H_(2)O_(2)Fenton-like system degrade phenol in the water,nano-Fe3 O4 composites which were loaded on the acid-modified vermiculite were prepared by solvothermal method.The morphology and valence of the catalysts were characterized by XRD,BET,and XPS.The effects of solution initial pH,the concentration of H_(2)O_(2),and active species on the efficiency of phenol degradation were investigated.The results showed that the degradation efficiency of 50 mg/L phenol activated by Fe_(3)O_(4)-MVerm reached 100%in 20 min when the dosage of Fe_(3)O_(4)-MVerm was 0.2 g/L,the solution pH was 4 and the dosage of H_(2)O_(2)was 5 mol/L.The activator can be effectively recycled by magnetic separation.In comparison with nano-Fe_(3)O_(4)particles,Fe_(3)O_(4)-MVerm effectively improved the agglomeration phenomenon of nano-Fe_(3)O_(4)particles,raised the ratio of Fe^(2+)/Fe^(3+)in the activator,expanded its specific surface area,and thus enhanced the Fenton-like oxidation performance of Fe_(3)O_(4).Hydroxyl radical quenching experiments demonstrated that the hydroxyl radicals bound to the surface of activators are mainly active species responsible for the degradation of phenol.After adding Fe_(3)O_(4)-MVerm for 20 min,the iron dissolution amount in the solution was 11.09 mg/L,while after directly adding pure Fe_(3)O_(4),the iron dissolution amount in the solution was 30.21 mg/L,significantly reducing the iron dissolution amount.The efficiency of the Fe_(3)O_(4)-MVerm/H_(2)O_(2)system degrade phenol still reached 62%after being reused three times,which showed superior degradation performance,catalytic stability,and the great ability to reuse.Besides,the compound material has economic benefits because the raw material SiO_(2) is cheap.Based on the above experimental results,Fe_(3)O_(4)-MVerm has promising potential in the treatment of wastewater containing phenol.

关 键 词：环境工程学 类FENTON Fe_(3)O_(4)-改性蛭石 苯酚 磁性 

分 类 号：X703.5[环境科学与工程—环境工程]