改性高岭土基非均相Fenton催化剂降解罗丹明B染料废水的研究

Research of modified kaolin based heterogeneous Fenton catalyst degrading rhodamine B dye in wastewater

以焙烧、酸浸改性后的高岭土作为非均相芬顿(Fenton)催化剂的载体,采用共沉淀法制得高岭土-三氧化二铁(Fe_2O_3)/二氧化锰(MnO_2)非均相Fenton催化剂,并于高岭土-Fe_2O_3/MnO_2、紫外光、过氧化氢(H_2O_2)的反应体系中高效降解罗丹明B(RhB)染料废水。利用X射线荧光光谱分析(XRF)、X射线衍射(XRD)、扫描电子显微镜(SEM)、能谱分析仪(EDS)以及X射线光电子能谱(XPS)对催化剂的结构和化学组成进行了表征。研究结果表明:在高岭土-Fe_2O_3/MnO_2用量为0.1g/L,反应温度25℃,H_2O_2用量为10.0mmol/L,溶液初始pH=3.0,RhB初始浓度为90.0mg/L,反应30min条件下,RhB的脱色率达到99.12%,运用一级动力学方程对反应过程进行拟合,R2=0.99,速率常数为0.159min^(-1)。

KaoIin was modified by roasting and acid leaching,and the modified kaolin was used as a supporter of heterogeneous Fenton catalyst.The kaolin-Fe2O3/MnO2heterogeneous Fenton catalyst was prepared by coprecipitation method,and rhodamine B(RhB)dye in wastewater was degraded efficiently in the reaction system of kaolin-Fe2O2/ MnO2,UV and H2O2.The chemical composition and structural characterization of catalyst was analyzed by X-ray fluorescence spectrometry (XRF),X-ray powder diffraction (XRD),scanning electron microscopy (SEM),energy dispersive spectrometry(EDS)and X-ray photoelectron spectroscopy(XPS).The results showed that the decolorization rate of RhB was 99.12%under agitation after 30min treatment with dosage of kaolin-Fe2O3/MnO20.1g/L,reaction temperature 25℃,dosage of H20210.0mmol/L,pH of 3.0and initial concentration of RhB 90.0mg/L.The first-order kinetic equation Was used to fit the reaction process and the rate constant was 0.159min^-1,R^2=0.99.