Synthesis, characterisation and application of TiO2–zeolite nanocomposites for the advanced treatment of industrial dye wastewater

Abstract

Photocatalysis usually involves the utilisation of nano-sized semiconductor photocatalysts owing to their higher specific surface area and surface reaction rate. However, the key challenges in the utilisation of nano-sized photocatalysts for advanced treatment of industrial dye wastewater are to enhance the post-separation and recovery of spent photocatalysts to prevent them from diffusing into the environment. Thus, the main aim of this study was to synthesize a functional-form of titanium dioxide (TiO2)–zeolite nanocomposite through the modified two-step sol–gel method for enhanced application and separation after advanced industrial dye wastewater treatment. The synthesized TiO2–zeolite nanocomposite was characterised using field-emission scanning electron microscopy (FE-SEM), energy dispersive X-ray (EDX) analysis, Fourier-transformed infrared spectroscopy (FTIR), particle size distribution analysis and Brunauer–Emmett–Teller (BET) specific surface area and porosity analysis. Subsequently, the photoactivity of synthesized TiO2–zeolite nanocomposite was measured and compared against the commercial TiO2 particles. It was found that the TiO2–zeolite nanocomposite shows a high apparent pseudo-first order reaction rate constant of 0.0419 min−1 at lower dye concentration. This showed that the synthesized TiO2–zeolite nanocomposite follows a more adsorption-oriented photocatalytic degradation of water pollutants, which is useful for removing trace and untreated dye compounds in the advanced industrial dye wastewater treatment stage.