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.
Sci Rep. 2017 Feb 23;7:43051. doi: 10.1038/srep43051.
Composite of nanoscale Zero Valent Iron (nZVI) loaded on Biochar (BC) was prepared and characterized as hydrogen peroxide (HO) activator for the degradation of trichloroethylene (TCE). nZVI is homogeneously loaded on lamellarly structured BC surfaces to form nZVI/BC with specific surface area (S) of 184.91 m g, which can efficiently activate HO to achieve TCE degradation efficiency of 98.9% with TOC removal of 78.2% within 30 min under the conditions of 0.10 mmol L TCE, 1.13 g L nZVI/BC and 1.50 mmol L HO. Test results from the Electron Spin Resonance (ESR) measurement and coumarin based fluorescent probe technology indicated that ∙OH radicals were the dominant species responsible for the degradation of TCE within the nZVI/BC-HO system. Activation mechanism of the redox action of Fe/Fe generated under both aerobic and anaerobic conditions from nZVI and single electron transfer process from BC surface bound C-OH to HO promoted decomposition of HO into ∙OH radicals was proposed.
负载纳米零价铁(nZVI)的生物炭(BC)复合材料被制备并表征为过氧化氢(HO)的激活剂,用于降解三氯乙烯(TCE)。nZVI 均匀负载在层状结构的 BC 表面上,形成比表面积(S)为 184.91 m g 的 nZVI/BC,在 0.10 mmol L TCE、1.13 g L nZVI/BC 和 1.50 mmol L HO 的条件下,可在 30 min 内将 TCE 的降解效率提高到 98.9%,TOC 去除率达到 78.2%。来自电子顺磁共振(ESR)测量和香豆素荧光探针技术的测试结果表明,在 nZVI/BC-HO 体系中,∙OH 自由基是降解 TCE 的主要物种。提出了在有氧和无氧条件下由 nZVI 产生的 Fe/Fe 的氧化还原作用的活化机制以及从 BC 表面结合的 C-OH 到 HO 的单电子转移过程,促进了 HO 分解为 ∙OH 自由基。