Surface functionalization of rutile TiO2 extracted from Egyptian ilmenite with titanosilicate for enhanced photocatalytic and ion removal performance

Abstract

This study investigates the surface modification of rutile TiO₂,extracted from local ilmenite ore, by amorphous titanosilicates to enhance its photocatalytic and ion exchange properties. The modification was achieved using titanium oxide, and commercial sodium silicate. The modified samples were characterized by various techniques, including X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), BET surface area analysis, Diffuse reflectance UV–Vis spectra, and Fourier-transform infrared spectroscopy (FTIR). Photocatalytic degradation of methylene blue and ion exchange for metal ions (Cu²⁺, Pb²⁺, Hg²⁺, and Cd²⁺) were evaluated to assess the performance of the modified materials. Sample 2, which showed the highest surface area and mesoporosity, exhibited superior photocatalytic activity and enhanced metal ion removal, particularly for Pb²⁺. Sample 3, which contained silica, demonstrated poor adsorption and degradation capabilities due to blocked active sites. This work highlights the significant impact of structural modifications on the photocatalytic and adsorption properties of TiO₂, offering an economically viable approach for large-scale environmental applications by using ilmenite and sodium silicate.