Biochar/Zeolite-Supported TiO2 Nanocatalyst for the Photodegradation of Organic Pollutants in Aqueous Media
摘要
Methylene blue colorant (MB) is commonly found in wood, cotton, and silk dyeing, and is thought to pose a concern hazardous to both humans and the environment. This study aims to synthesize zeolite and biochar (BC) nanomaterials from plentiful by-products and olive stone (OS) using recycling hydrothermal and pyrolysis routes to photodegrade MB, addressing environmental challenges. The obtained products were characterized by X-ray diffraction, scanning electron microscopy, energy dispersive spectroscopy, and organic carbon analysis. Complementary investigations into textural properties were carried out via surface area and cation exchange capacity (CEC) measurements. The results showed that under specific conditions of 140 °C, NaOH 1.5 M, Si/Al ratio 4, and 36 h, the zeolitization content reached 84% with a surface area of 66.54 m2/g and a CEC of 37 meq/100 g. Additionally, the BC produced has a mass yield of 30.7% and a surface area of 17 m2/g. Meanwhile, a photocatalyst was prepared by mechanically mixing BC, zeolite, and TiO2 followed by calcination (300 °C, 3 h) for photodegradation of MB. The BC/zeolite-loaded TiO2 showed better performance in the photocatalysis process with high degradation efficiency (95.81% for 60 mg/L of MB) over 3 uses with the generation of responsible hydroxyl radicals (OH·). Preliminary results on the photocatalysis of MB showed that the BC/zeolite-loaded TiO2 nanocomposite could be a potential material for application in wastewater treatment offering promising wastes valorization without harming the environment.
Graphical Abstract