| 高晶度Mn-Fe LDH催化剂活化过一硫酸盐降解偶氮染料RBK5 |
| 摘要点击 1492 全文点击 658 投稿时间：2019-12-15 修订日期：2020-01-13 |
| 查看HTML全文
查看全文 查看/发表评论 下载PDF阅读器 |
| 中文关键词 锰铁层状双金属氢氧化物(Mn-Fe LDH) 过一硫酸盐(PMS) 活性黑5 协同作用 高级氧化 |
| 英文关键词 Mn-Fe layered double hydroxide(Mn-Fe LDH) peroxymonosulfate(PMS) reactive black 5 synergistic effect advanced oxidation process |
| 作者 | 单位 | E-mail | | 李立 | 华侨大学化工学院, 厦门 361021
福建省工业废水生化处理工程技术研究中心, 厦门 361021 | 13375929507@163.com | | 吴丽颖 | 华侨大学化工学院, 厦门 361021
福建省工业废水生化处理工程技术研究中心, 厦门 361021 | | | 董正玉 | 华侨大学化工学院, 厦门 361021
福建省工业废水生化处理工程技术研究中心, 厦门 361021 | | | 王霁 | 华侨大学化工学院, 厦门 361021
福建省工业废水生化处理工程技术研究中心, 厦门 361021 | | | 张倩 | 华侨大学化工学院, 厦门 361021
福建省工业废水生化处理工程技术研究中心, 厦门 361021 | | | 洪俊明 | 华侨大学化工学院, 厦门 361021
福建省工业废水生化处理工程技术研究中心, 厦门 361021 | jmhong@hqu.edu.cn |
|
| 中文摘要 |
| 采用改进的共沉淀结合水热法制备高晶度锰铁层状双金属氢氧化物作为催化剂，用于高效活化过一硫酸盐（PMS）降解活性黑5（RBK5）.通过X射线粉末衍射仪（XRD）、扫描电子显微镜（SEM）、X射线能谱分析（EDS）、傅里叶变换红外光谱仪（FTIR）以及X射线光电子能谱（XPS）对材料进行表征，证明成功合成了结晶度高、层状结构突出的Mn-Fe LDH.同时探究了锰铁量比，催化剂投加量，PMS浓度和初始pH值等因素对RBK5的吸附效果、催化降解及反应动力学的影响.结果表明，高晶度Mn-Fe LDH催化剂具有良好的吸附能力和高效的催化效率，在n（Mn）/n（Fe）比为1：1，催化剂投加量为0.2 g·L-1，PMS浓度为1 mmol·L-1，初始pH为7时，RBK5（20 mg·L-1）在90 min内降解率可达86%，整个反应过程符合拟一级动力学（R2>0.9）.自由基猝灭实验表明，Mn-Fe LDH/PMS体系降解RBK5为SO4-·和·OH两种活性自由基共同作用的结果.反应前后催化剂的XPS分析表明Mn和Fe存在协同作用，Mn-Fe LDH的Mn（Ⅱ）和Fe（Ⅲ）与层间的CO32-电荷平衡，使其层状结构稳定，从而促进了层状表面Mn和Fe的协同作用，提高了Mn-Fe LDH对PMS的活化效率.三维荧光光谱（3D-EEM）和UV-Vis扫描光谱分析初步探讨了RBK5的降解过程. |
| 英文摘要 |
| High crystallinity Mn-Fe LDH was synthesized by improved co-precipitation combined with the hydrothermal method and was utilized as a catalyst for peroxymonosulfate (PMS) activation to degrade reactive black 5. The high crystal purity and clear lamellar structure were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), energy dispersive X-ray spectrometer (EDS), Fourier transform infrared spectroscopy (FTIR), and X-ray photoelectron spectroscopy (XPS). The operating parameters such as Mn/Fe molar ratio, catalyst dosage, PMS concentration, and initial pH value on the absorption efficiency, catalytic degradation, and reaction kinetics of RBK5 were also investigated. The results demonstrated that high crystallinity Mn-Fe LDH has good adsorption capacity and high catalytic efficiency. The degradation efficiency of RBK5 (20 mg·L-1) could reach 86% within 90 min when the Mn/Fe molar ratio was 1, the catalyst dosage was 0.2 g·L-1, the PMS concentration was 1 mmol·L-1, and the initial pH value was 7.0. The reaction process follows pseudo-first-order reaction kinetics (R2>0.9). In addition, the quenching experiment indicated that SO4-·and·OH were the main active species that degraded RBK5 from the Mn-Fe LDH/PMS system. The XPS analysis of the catalyst before and after the reaction confirmed the synergistic effect between Mn and Fe. The charge balance between Mn(Ⅱ) and Fe(Ⅲ) on the LDH surface and CO32- in layers stabilized the structure, thus promoting the synergistic effect of Mn and Fe on the lamellar surface and improving the activation efficiency of PMS by Mn-Fe LDH. Three-dimensional fluorescence and the UV-Vis scanning spectral analysis were preliminarily discussed to understand the degradation process of RBK5. |
|
|
|
