Ji Qingqing, Li Jun, Xiong Zhaokun, Lai Bo
Department of Environmental Science and Engineering, School of Architecture and Environment, Sichuan University, Chengdu 610065, China.
Department of Environmental Science and Engineering, School of Architecture and Environment, Sichuan University, Chengdu 610065, China.
Chemosphere. 2017 Apr;172:10-20. doi: 10.1016/j.chemosphere.2016.12.128. Epub 2016 Dec 27.
In this study, batch experiments were conducted to examine the enhanced reactivity of microscale Fe/Cu bimetallic particles (mFe/Cu) with persulfate (PS) for p-nitrophenol (PNP) removal in aqueous solution. The key operating parameters (i.e., theoretical Cu mass loadings (TML), mFe/Cu dosage, PS dose, initial pH and temperature) were optimized by the batch experiments, respectively. The experimental data were followed well the pseudo-first-order kinetic model. Result reveals that refractory PNP (500 mg L) was effectively degraded by mFe/Cu-PS system with removal of 98.4% and k of 1.91 min after only 3 min treatment under the optimal operating conditions. Moreover, compared with control experiments (i.e., mFe/Cu, microscale Fe with PS (mFe-PS), and PS alone), mFe/Cu-PS system exerted better performance for PNP removal due to the strong synergistic effect between PS and mFe/Cu. According to the analysis results of degradation kinetics of PNP, COD (chemical oxygen demand) removal, UV-vis absorption spectra and the intermediates formed, the results reveal that the PNP removal by mFe/Cu-PS system was mainly attributed to reduction accompanied slight oxidation. And based on the analysis of surface characteristics of mFe/Cu particles, it is further demonstrated that PS could enhance the reactivity of mFe/Cu through rapid corrosion of iron surface and decrease of surface passivation of mFe/Cu surface when the low molar ratio of PS to mFe/Cu (i.e., 1:43) was used in this study. These results also illustrates mFe/Cu-PS can be as a high efficient pretreatment technology for the removal of toxic refractory PNP from wastewater.
在本研究中，进行了批次实验，以考察微尺度铁铜双金属颗粒（mFe/Cu）与过硫酸盐（PS）对水溶液中对硝基苯酚（PNP）去除的增强反应活性。通过批次实验分别优化了关键操作参数（即理论铜质量负载（TML）、mFe/Cu投加量、PS投加量、初始pH值和温度）。实验数据很好地符合伪一级动力学模型。结果表明，在最佳操作条件下，仅经过3分钟处理，难降解的PNP（500 mg/L）就被mFe/Cu-PS体系有效降解，去除率达98.4%，k为1.91 min⁻¹。此外，与对照实验（即mFe/Cu、微尺度铁与PS（mFe-PS）以及单独的PS）相比，由于PS与mFe/Cu之间的强协同效应，mFe/Cu-PS体系对PNP的去除表现出更好的性能。根据PNP降解动力学、化学需氧量（COD）去除、紫外可见吸收光谱以及形成的中间产物的分析结果，结果表明mFe/Cu-PS体系对PNP的去除主要归因于还原并伴有轻微氧化。并且基于对mFe/Cu颗粒表面特性的分析，进一步证明当本研究中使用低摩尔比的PS与mFe/Cu（即1:43）时，PS可通过快速腐蚀铁表面并减少mFe/Cu表面的钝化来增强mFe/Cu的反应活性。这些结果还表明mFe/Cu-PS可作为一种高效的预处理技术，用于从废水中去除有毒难降解的PNP。
