Removal of toluene on BiOI/activated carbon via adsorption/photocatalysis synergistically

Volatile organic compounds (VOCs) are important pollutants that affect the environmental air quality. In this work, BiOI/activated carbon (BiOI/AC) composites were prepared by simple impregnation method to remove toluene, which is a representative VOC. The as-prepared samples were characterized by SEM, XRD, BET, XPS and UV-vis-DRS. The result showed that tetragonal BiOI with strong light absorption ability was anchored onto the surface of AC uniformly. The adsorption removal, adsorption/photocatalytic degradation removal of toluene by 4%BiOI/AC were 20.7% and 92.95% within 160 min respectively when experimental conditions were 100 mL·min⁻¹ of gas flow, 1600 mg·m⁻³ of initial concentration of toluene. Under the same experimental conditions, the lowest adsorption/photocatalytic removal rate of toluene on 2%BiOI/AC composite could reach 95.46%. Most importantly, adsorption sites of AC could be regenerated by BiOI photocatalysis, which can enhance the usage time of the composite and lower and usage cost.