Preparation of TiO2 supported on MDF biochar for simultaneous removal of methylene blue by adsorption and photocatalysis

Abstract BACKGROUND This article reports for the first time the preparation and characterization of biochar/titanium dioxide (TiO 2 ) composites by pyrolysis from medium‐density fiberboard (MDF) biomass. Their adsorptive and photocatalytic activities were evaluated by removal of methylene blue (MB) dye from aqueous solutions with and without UV‐light irradiation. RESULTS Characterization results suggested that the composite have different intrinsic characteristics in relation to the precursors. The biochar and TiO 2 amounts of the composite significantly affected its performance. The MB removal efficiency with 1 g L −1 of the composite with 10% w / w TiO 2 (B10T sample) was 2.3 and 2.2 times faster than that the B5T and B1T samples, respectively, and 1.5 times faster than TiO 2 alone. CONCLUSION The loading of TiO 2 significantly enhanced the adsorption performance of the composite and factors such as specific surface area, pore volume and pore size of the biochar synergistically promoted the photocatalytic activity of TiO 2 , coupled with a lower band gap for all composites produced. Both adsorption and photocatalytic efficiencies were confirmed to contribute to the degradation of the aqueous solution of MB by the hydroxyl radical ( • OH) in lower molecular mass by‐products. The synthesized composite is a promising alternative sustainable material for removing chemical contaminants, since the biochar used as a support comes from the waste of the furniture industry. © 2019 Society of Chemical Industry