钴强化铁磁体活化过一硫酸盐的实验研究

Experimental study on activation of peroxymonosulfate by cobalt-enhanced ferromagnet

采用溶剂热法后高温煅烧的方式制备了铁钴双金属复合催化剂,用以活化过一硫酸盐(PMS)降解偶氮染料金橙Ⅱ(OGⅡ)。通过X射线衍射仪、扫描电子显微镜、振动样品磁强计和X射线光电子能谱仪等仪器对复合材料进行了表征。考察了钴复合量、不同去除体系、催化剂投加量、PMS投加量、污染物浓度、pH和共存阴离子等因素对OGⅡ降解效果的影响,并探究了铁钴复合催化剂重复利用的效果。实验结果表明,铁钴复合催化剂可以有效活化PMS降解OGⅡ,在n(Co_(3)O_(4))∶n(Fe_(2)O_(3))=0.1、催化剂投加量为1.0 g/L、PMS投加量为0.4 mmol/L、OGⅡ浓度为30 mg/L、溶液pH为6.2的条件下,反应60 min后,OGⅡ的降解率达到了95.81%,其降解过程符合准一级反应动力学模型,最大反应速率常数为0.0491 min^(-1)。复合催化剂使用4次后对OGⅡ仍有68.85%的降解率。·SO^(-)_(4)、·OH和^(1)O_(2)是反应体系产生的活性氧物种,^(1)O_(2)在OGⅡ的降解中起主要作用。

The iron-cobalt bimetallic composite catalyst was prepared by solvothermal method followed by high temperature calcination to activate peroxymonosulfate(PMS)to degrade the azo dye orangeⅡ(OGⅡ).The composites were characterized by X-ray diffractometer,scanning electron microscope,vibrating sample magnetometer and X-ray photoelectron spectrometer.The effects of cobalt compound amount,different removal systems,catalyst dosage,PMS dosage,pollutant concentration,pH and coexisting anions on the degradation effect of OGⅡwere investigated,and the reuse effect of iron-cobalt composite catalyst was explored.The experimental results show that the iron-cobalt composite catalyst can effectively activate PMS to degrade OGⅡ.When n(Co_(3)O_(4))∶n(Fe_(2)O_(3))=0.1,the dosage of catalyst is 1.0 g/L,the dosage of PMS is 0.4 mmol/L,the concentration of OGⅡis 30 mg/L and pH of solution is 6.2,after 60 min of reaction,the degradation rate of OGⅡreached 95.81%,the degradation process conformed to the pseudo-first-order kinetic model,and the maximum reaction rate constant was 0.0491 min^(-1).The composite catalyst still had a degradation rate of 68.85%to OGⅡafter 4 cycles.·SO^(-)_(4),·OH and ^(1)O_(2) are reactive oxygen species produced in the reaction system,and ^(1)O_(2) plays a major role in the degradation of OGⅡ.