Ouyang Da, Yan Jingchun, Qian Linbo, Chen Yun, Han Lu, Su Anqi, Zhang Wenying, Ni Hao, Chen Mengfang
Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China; University of Chinese Academy of Sciences, Beijing 100049, China.
Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China.
Chemosphere. 2017 Oct;184:609-617. doi: 10.1016/j.chemosphere.2017.05.156. Epub 2017 May 30.
Nano magnetite biochar composite (nFeO/biochar) was synthesized and used to activate persulfate for the degradation of 1,4-dioxane. Analytical techniques using X-ray diffraction (XRD), fourier transform infrared analysis (FTIR), X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM) indicated that nFeO was spherical and successfully loaded onto the surface of biochar. The results of batch-scale experiments illustrated that the 1,4-dioxane degradation efficiency in aqueous phase was 98.0% after 120 min reaction with the composite mass ratio of 1:1 between nFeO and the pine needle biochar pyrolyzed at 400 °C (P400) under the initial neutral pH. An electron paramagnetic resonance (EPR) study, free radical quenching experiment and XPS analysis were undertaken to illustrate the mechanism of persulfate activation by nFeO/biochar. Under acidic and neutral conditions, the predominant free radical was SO whereas OH and SO predominated when the initial pH was 9.0. The XPS analysis indicated that Fe(II) and oxygenated functional groups activated persulfate. In addition, carbon-carbon double bonds would be transformed into ketone and quinone which could activate persulfate during the reaction.
合成了纳米磁铁矿生物炭复合材料（nFeO/生物炭），并用于活化过硫酸盐以降解1,4-二氧六环。采用X射线衍射（XRD）、傅里叶变换红外分析（FTIR）、X射线光电子能谱（XPS）和扫描电子显微镜（SEM）等分析技术表明，nFeO呈球形并成功负载在生物炭表面。批次实验结果表明，在初始中性pH值条件下，nFeO与400℃热解的松树针叶生物炭（P400）质量比为1:1的复合材料反应120分钟后，水相中1,4-二氧六环的降解效率为98.0%。进行了电子顺磁共振（EPR）研究、自由基猝灭实验和XPS分析，以阐明nFeO/生物炭活化过硫酸盐的机制。在酸性和中性条件下，主要自由基为SO，而初始pH为9.0时，OH和SO占主导地位。XPS分析表明，Fe(II)和含氧官能团活化了过硫酸盐。此外，碳-碳双键在反应过程中会转化为酮和醌，从而活化过硫酸盐。
