Fe^(0)@Fe_(3)O_(4)/火山岩催化H_(2)O_(2)氧化亚甲基蓝脱色研究  

Decolorization study of methylene blue oxidation by H_(2)O_(2) catalyzed by Fe^(0)@Fe_(3)O_(4)/volcanic rock

作　　者：国洁[1,2] 宋佳乐 侯永江 梁茹茹[1,2] GUO Jie;SONG Jiale;HOU Yongjiang;LIANG Ruru(School of Environmental Science and Engineering,Hebei University of Science and Technology,Shijiazhuang 050018,China;Pollution Prevention Biotechnology Laboratory of Hebei Province,Shijiazhuang 050018,China)

机构地区：[1]河北科技大学环境科学与工程学院,石家庄050018 [2]河北省污染防治生物技术实验室,石家庄050018

出　　处：《安全与环境学报》2023年第12期4498-4506,共9页Journal of Safety and Environment

基　　金：河北省高等学校科学技术研究项目(ZD2017233)。

摘　　要：以火山岩为载体,采用化学沉淀法和液相还原法制备Fe~0@Fe_(3)O_(4)/火山岩催化剂,结合X射线衍射(XRD)、透射电子显微镜(TEM)、傅里叶变换红外光谱(FT-IR)和比表面积测试(BET)进行表征,并通过亚甲基蓝(Methylene Blue,MB)模拟废水试验对催化剂活性进行评价。XRD结果显示,两种方法制得的催化剂中有明显的铁氧化物和零价铁衍射峰;TEM结果显示,Fe~0和Fe_(3)O_(4)以核壳结构分布在火山岩表面;BET结果显示,Fe~0@Fe_(3)O_(4)/火山岩的比表面积是火山岩的5倍,且孔容和孔径都有所增加。利用火山岩自身铁元素质量分数高的特性,对火山岩改性并制备Fe~0@Fe_(3)O_(4)/火山岩催化剂,制得的催化剂能够有效地催化废水中的MB脱色,成本低且3 h的脱色率可达98.47%。Fe~0@Fe_(3)O_(4)/火山岩催化剂提高了MB的矿化度并具有较高的可重复利用价值,催化氧化系统主要遵循羟基自由基的反应机理。The Fe^(0)@Fe_(3)O_(4)/volcanic rock catalyst was prepared by chemical precipitation and liquid phase reduction using the volcanic rock as the carrier and characterized by XRD,TEM,BET,and FT-IR,and the catalyst activity was evaluated by simulated methylene blue(MB) wastewater experiments.The XRD results showed that there were obvious diffraction peaks of Fe_(3)O_(4) and Fe^(0) in the catalyst prepared by the two methods;the TEM results showed that Fe^(0) and Fe_(3)O_(4) are distributed on the surface of the volcanic rock in a core-shell structure;the BET results showed that the specific surface area of Fe^(0)@Fe_(3)O_(4)/volcanic rock was about 5 times that of the original volcanic rock;the electronegative functional groups on the catalyst can adsorb Fe^(2+) in the solution during the preparation of Fe^(0),facilitating the Fe^(0) loading.The catalyst was prepared by taking advantage of the fact that the volcanic rock itself has the highest content of iron as a metal element.The prepared catalyst was effective in catalyzing the decolorization of MB in wastewater,with the highest decolorization rate at a molar ratio of Fe^(0) to Fe_(3)O_(4) of 1:1 in the pores.At a reaction temperature of 25 ℃,H_(2)O_(2) addition of 2 mL,catalyst dosage of 0.5 g,and pH = 5,the decolorization rate of MB was 98.47% at 180 min.The adsorption process conformed to the quasi-secondary kinetic model with a saturation adsorption capacity of 19.43 mg/g and an initial adsorption rate of 2.04 mg/(g·min).The results of the quenching experiment confirmed the strong oxidation of ·OH,and also verified that ·OH was the main reactive oxide(ROS) produced in the reaction system catalyzing H_(2)O_(2) oxidation and decolorization of MB.The EPR results showed that Fe^(0)@Fe_(3)O_(4) was able to activate the volcanic rocks to produce ·OH and ·OH was the main reactive material,the catalytic oxidation system mainly followed the reaction mechanism of ·OH,and the EPR characterization confirmed the results of the quenching experiment.Fe^(0)@Fe_(3)O_(4

关 键 词：环境工程学 催化化学 Fe^(0)@Fe_(3)O_(4)/火山岩 催化氧化 亚甲基蓝 

分 类 号：X703[环境科学与工程—环境工程]