Li Renchao, Gao Ying, Jin Xiaoying, Chen Zuliang, Megharaj Mallavarapu, Naidu Ravendra
School of Environment Science and Engineering, Fujian Normal University, Fuzhou 350007, Fujian Province, China.
School of Environment Science and Engineering, Fujian Normal University, Fuzhou 350007, Fujian Province, China; Centre for Environmental Risk Assessment and Remediation, University of South Australia, Mawson Lakes, SA 5095, Australia; Cooperative Research Centre for Contamination Assessment and Remediation of Environments, Mawson Lakes, SA 5095, Australia.
J Colloid Interface Sci. 2015 Jan 15;438:87-93. doi: 10.1016/j.jcis.2014.09.082. Epub 2014 Oct 13.
In this report, various iron-based nanoparticles (nZVI, n-Ni/Fe, n-Pd/Fe) were used for both heterogeneous Fenton oxidation of 2,4-dichlorophenol (2,4-DCP) and reductive dechlorination of 2,4-DCP in order to understand their roles in the Fenton oxidation and the reductive degradation of 2,4-DCP. The dechlorination efficiency of 2,4-DCP using nZVI, n-Ni/Fe, n-Fe/Pd and Fe(2)(+) was 6.48%, 6.80%, 15.95%, 5.02%, while Fenton oxidation efficiency of 2,4-DCP was 57.87%, 34.23%, 27.94%, 19.61% after 180 min, respectively. The new findings included a higher dechlorination using n-Fe/Pd due to Pd effective catalysis and the effective heterogeneous Fenton oxidation using nZVI depending on reductive dechlorination and heterogeneous Fenton oxidation occurs simultaneously. However, nZVI as the potential catalyst for heterogeneous Fenton was observed, and SEM, EDS and XRD demonstrate that change on the nZVI surface occurred due to the Fe(2+) leaching, and Total Organic Carbon (TOC) (30.71%) shows that 2,4-DCP was degraded. Furthermore, the experiment indicates that the pH values and concentration of 2,4-DCP significantly impacted on the heterogeneous Fenton oxidation of 2,4-DCP and the data fits well with the pseudo first-order kinetic model, which was a diffusion-controlled reaction. Finally, a possible mechanism for degradation of 2,4-DCP was proposed.
在本报告中，使用了各种铁基纳米颗粒（纳米零价铁、镍铁纳米颗粒、钯铁纳米颗粒）对2,4 - 二氯苯酚（2,4 - DCP）进行非均相芬顿氧化以及对2,4 - DCP进行还原脱氯，以了解它们在2,4 - DCP的芬顿氧化和还原降解中的作用。使用纳米零价铁、镍铁纳米颗粒、钯铁纳米颗粒和亚铁离子对2,4 - DCP的脱氯效率分别为6.48%、6.80%、15.95%、5.02%，而180分钟后2,4 - DCP的芬顿氧化效率分别为57.87%、34.23%、27.94%、19.61%。新发现包括由于钯的有效催化作用，钯铁纳米颗粒的脱氯效果更好，以及纳米零价铁由于还原脱氯和非均相芬顿氧化同时发生而实现了有效的非均相芬顿氧化。然而，观察到纳米零价铁作为非均相芬顿的潜在催化剂，扫描电子显微镜（SEM）、能谱仪（EDS）和X射线衍射仪（XRD）表明，由于亚铁离子的浸出，纳米零价铁表面发生了变化，总有机碳（TOC）（30.71%）表明2,4 - DCP被降解。此外，实验表明pH值和2,4 - DCP的浓度对2,4 - DCP的非均相芬顿氧化有显著影响，数据与伪一级动力学模型拟合良好，这是一个扩散控制反应。最后，提出了2,4 - DCP降解的可能机制。
