Enhanced Fenton-like Degradation of Trichloroethylene by Hydrogen Peroxide Activated with Nanoscale Zero Valent Iron Loaded on Biochar

Abstract

Abstract Composite of nanoscale Zero Valent Iron (nZVI) loaded on Biochar (BC) was prepared and characterized as hydrogen peroxide (H 2 O 2 ) 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 BET ) of 184.91 m 2 g −1 , which can efficiently activate H 2 O 2 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 −1 TCE, 1.13 g L −1 nZVI/BC and 1.50 mmol L −1 H 2 O 2 . 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-H 2 O 2 system. Activation mechanism of the redox action of Fe 2+ /Fe 3+ generated under both aerobic and anaerobic conditions from nZVI and single electron transfer process from BC surface bound C–OH to H 2 O 2 promoted decomposition of H 2 O 2 into ∙OH radicals was proposed.