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

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 same pyrolysis temperature 600 °C. Analyses via X-ray absorption near-edge spectroscopy, photoelectron Raman spectroscopy revealed that both contained species such as Fe3O4, FeOOH, Fe2O3, having more reduced Fe(II) Fe-AC. This result is clear evidence had better catalytic activity MB The efficiencies total organic by prepared optimum concentration (0.25 M Fe) were 98.3 % 46.3 %, respectively. In particular, predominantly degradation due to HFR, while adsorption dominant case impregnation) showed treatment (≥ 65.7 %) stable release ions (< 2 mg/L) during 5 consecutive HFR reactions. Low-temperature (prepared 200 °C) poor instability reusability. view above results, can be used an economic catalyst because it has superior stability recyclability treating recalcitrant pollutants