REMOVAL OF METHYLENE BLUE FROM AQUEOUS SOLUTION USING TiO2/SiO2/CMC PHOTOCATALYTIC COMPOSITE MATERIALS

Abstract

In this study, the composite material made from TiO₂, SiO₂, and CMC was synthesized using the sol-gel method. The structure of the material was characterized by various techniques, including X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), energy-dispersive spectroscopy (EDS), scanning electron microscopy (SEM), UV-Vis diffuse reflectance spectroscopy (UV-Vis DRS), and dynamic light scattering (DLS). The results indicated that the synthesized TiO₂/SiO₂/CMC material had a spherical shape with a fairly uniform size distribution in the range of 90–100 nm.The applicability of the TiO₂/SiO₂ and TiO₂-SiO₂/CMC composite materials for degrading Methylene Blue under both illuminated and non-illuminated conditions was evaluated using the UV-Vis method. The results showed that, with a material mass materials of 0.05 g and an initial dye concentration (C_MB) below 20 ppm, the dye was completely degraded. Furthermore, for CMB concentrations in the range of 100–200 ppm, with m= 0.1–0.2 g and t = 60 minutes under illumination, the degradation efficiency reached 97%, whereas under non-illuminated conditions, it was 93%. For the TiO₂/SiO₂ material, the corresponding values were 92% and 87%, respectively.Thus, it can be observed that under the same experimental conditions, the TiO₂/SiO₂ composite with a CMC coating exhibited better dye degradation performance than the TiO₂/SiO₂ composite, both under illuminated and non-illuminated conditions. Additionally, under illumination, the degradation efficiency increased by 8–10% compared to non-illuminated conditions. The kinetics of the degradation reaction were studied based on the Langmuir-Hinshelwood model.