Fe2O3/TiO2 functionalized biochar as a heterogeneous catalyst for dyes degradation in water under Fenton processes

Functionalized biochar as a great potential purification material towards removal of contaminants form environment. Herein, Fe2O3/TiO2 functionalized biochar (Fe2O3/TiO2-BC) was fabricated through one-step pyrolysis of Fe2+-Ti4+ laden tea leaves biomass under air environment. The morphology, structure, and chemical state of Fe2O3/TiO2-BC were systematically characterized. Fe2O3/TiO2-BC exhibits higher degradation efficiency for dye pollutants via synergistic effect of sorption and oxidation in the Fenton system. The total organic carbon (TOC) removal efficiencies reached above 65 %. The degradation mechanisms and pathways of dyes (methylene blue (MB) selected as model), and the effects of the amount of H2O2, catalyst dosage, temperature, and initial pH value on the degradation processes were also studied. The electron spin resonance (ESR) and radicals quenching experimental results confirmed that the dominant radical species was hydroxyl radical. Additionally, Fe2O3/TiO2-BC could be easily regenerated by washing with water/ethanol mixture. Overall, these results indicate that the Fe2O3/TiO2-BC provides great potential for removing dye pollutants from water.