铁酸钴复合碳纳米管活化过硫酸盐降解铬黑T的性能及机理  

Properties and mechanism of eriochrome black T degradation by carbon nanotube-cobalt ferrite composites activated persulfate

作　　者：龚鹏程 严群[1] 陈锦富 温俊宇 苏晓洁 GONG Pengcheng;YAN Qun;CHEN Jinfu;WEN Junyu;SU Xiaojie(School of Civil and Surveying&Mapping Engineering,Jiangxi University of Science and Technology,Ganzhou 341000,Jiangxi,China;Research Center for Water Quality Security Technology at Ganjiang River Basin,Jiangxi University of Science and Technology,Ganzhou 341000,Jiangxi,China)

机构地区：[1]江西理工大学土木与测绘工程学院,江西赣州341000 [2]江西理工大学赣江流域水质安全保障中心,江西赣州341000

出　　处：《化工进展》2023年第7期3572-3581,共10页Chemical Industry and Engineering Progress

基　　金：“十二五”国家科技支撑计划(2012BAC11B07);江西省科技厅自然科学基金(20122BAB203027)。

摘　　要：采用水热法制备了不同质量比铁酸钴/碳纳米管(CoFe_(2)O_(4)/CNT)复合材料,并将其用于活化过一硫酸盐(PMS)降解偶氮染料铬黑T(EBT)。使用扫描电镜、X射线衍射仪、X射线光电子能谱仪等方法进行了表征。结果表明,引入CNT改善了CoFe_(2)O_(4)团聚现象,同时CNT加速CoFe_(2)O_(4)表面电子转移过程进一步提高了CoFe_(2)O_(4)催化活性。质量比为4∶1的CoFe_(2)O_(4)/CNT表现出最高催化活性,CoFe_(2)O_(4)/CNT-4∶1+PMS降解EBT过程符合准一级动力学模型,其反应速率常数是CoFe_(2)O_(4)+PMS体系的2.02倍。单因素条件实验得出在CoFe_(2)O_(4)/CNT-4∶1投加量为0.20g/L、PMS投加量为0.20g/L、EBT质量浓度为100mg/L、pH为5.8、反应温度为25℃条件下,反应60min后EBT降解率可达到99.8%。CoFe_(2)O_(4)/CNT-4∶1循环使用三次后EBT降解率能达到67.8%。猝灭实验证明反应体系中存在着SO_(4)^(-)·、·OH、O_(2)^(-)·和^(1)O_(2)四种活性物质,其中^(1)O_(2)是主要活性物质。Fe^(2+)/Fe^(3+)、Co^(2+)/Co^(3+)价态循环和氧物种改变促进了活性物质生成。Cobalt ferrite and carbon nanotubes(CoFe_(2)O_(4)/CNT)composites with different mass ratios were prepared by hydrothermal method,and then used to activate persulfate(PMS)to degrade the azo dye eriochrome black T(EBT).Scanning electron microscope,X-ray diffractometer and X-ray photoelectron spectroscopy were used for sample characterization.The results showed that the introduction of CNT lessened the agglomeration of CoFe_(2)O_(4),and accelerated the electron transfer process on the surface of CoFe_(2)O_(4),and thus improved the catalytic activity.The CoFe_(2)O_(4)/CNT of mass ratio 4∶1 showed the highest catalytic activity,and the degradation process of EBT by CoFe_(2)O_(4)/CNT-4∶1+PMS was in accordance with the pseudo-first-order kinetics model,with the reaction rate constant 2.02 times higher than that of CoFe_(2)O_(4)+PMS system.Under the conditions of CoFe_(2)O_(4)/CNT-4∶1 dosage of 0.20g/L,PMS dosage of 0.20g/L,EBT concentration of 100mg/L,pH of 5.8 and the reaction temperature of 25℃,the degradation rate of EBT could reach 99.8% after 60min of reaction and could still reach 67.8% even when CoFe_(2)O_(4)/CNT-4∶1 had been reused for three times.Quenching experiments showed that there were four kinds of active substances in the reaction system,that is SO_(4)^(-)·,·OH,O_(2)^(-)·and ^(1)O_(2),among which ^(1)O_(2) was the dominant one.Valence cycle of Fe^(2+)/Fe^(3+)and Co^(2+)/Co^(3+)and oxygen species change promoted the formation of active substances.

关 键 词：铁酸钴 碳纳米管 活化作用 催化剂载体 降解 

分 类 号：X703[环境科学与工程—环境工程]