Comparison of catalytic activity for treating recalcitrant organic pollutant in heterogeneous Fenton oxidation with iron-impregnated biochar and activated carbon. (August 2021)

• Record Type: Journal Article
• Authors: Park, Jong-Hwan; Wang, Jim J.; Seo, Dong-Cheol
• Is Part Of: Journal of water process engineering. Volume 42(2021)
• Publication Date: 2021-08
• Subjects: Fenton-like reaction -- Recalcitrant pollutants -- Impregnation and pyrolysis -- Agricultural residue -- Heterogeneous Fenton reaction; Water-supply engineering -- Periodicals; Saline water conversion -- Periodicals; Seawater -- Distillation -- Periodicals; Sanitary engineering -- Periodicals; Sewage -- Purification -- Periodicals; 627
• DOI: 10.1016/j.jwpe.2021.102141
• Languages: English
• ISSNs: 2214-7144

Abstract

Abstract: Iron-impregnated biochar (Fe-BC) was developed through one-step pyrolysis, characterized, and directly compared with Fe-impregnated activated carbon (Fe-AC) for the removal of methylene blue (MB) in a heterogeneous Fenton reaction (HFR). Fe-BC exhibited significantly higher Fe impregnation efficiency than Fe-AC at the same pyrolysis temperature of 600 °C. Analyses via X-ray absorption near-edge spectroscopy, X-ray photoelectron spectroscopy, and Raman spectroscopy revealed that both Fe-BC and Fe-AC contained Fe species such as Fe3 O4, FeOOH, and Fe2 O3, with Fe-BC having significantly more reduced Fe(II) than Fe-AC. This result is clear evidence that Fe-BC had better catalytic activity for MB than Fe-AC. The removal efficiencies of MB and total organic carbon by Fe-BC and Fe-AC prepared with optimum Fe impregnation concentration (0.25 M Fe) were 98.3 % and 46.3 %, respectively. In particular, Fe-BC removal of MB was predominantly by degradation due to the HFR, while adsorption was dominant in the case of Fe-AC. In particular, Fe-BC (0.25 M Fe impregnation) showed higher MB treatment efficiency (≥ 65.7 %) and stable release of Fe ions (< 2 mg/L) compared to Fe-AC during 5 consecutive HFR reactions. Low-temperature Fe-AC (prepared at 200 °C) showed poor Fe impregnation and instability for reusability. In view of the above results, the developed Fe-BC can be used as an economic catalyst because it has superior stability and recyclability for treating recalcitrant pollutants compared to Fe-AC.