Polymeric Granules Supported Day–Night Photocatalyst-Based Filter for Wastewater Treatment

Establishing an environmentally friendly and sustainable purpose is essential for addressing significant environmental contaminants. In order to showcase the practicality of photocatalysis for environmental remediation, the selection of the catalyst, the method of utilization, and the reactor’s design are all equally essential factors. In this study, a visible light-activated day–night photocatalyst (g-C3N4@Gd2O3@CNT) was used to upgrade the efficiency; further, the catalyst was coated on polyurethane sponge granules to enhance the available surface area of the catalyst. Additionally, the innovative photoreactor comprises a flat reactor panel constructed from glass and loaded with g-C3N4@Gd2O3@CNT@PU catalytic granules. The degradation of methylene blue dye by photocatalysis in both the presence (93%) and absence of light (62%) confirmed the photocatalytic effectiveness of the g-C3N4@Gd2O3@CNT@PU. Operational conditions were optimized for the flat-packed bed reactor. Furthermore, at optimum conditions, the antimicrobial efficacy of the polymeric amalgam was evaluated against Escherichia. coli, demonstrating a remarkable ∼99% reduction in cell viability, thus affirming its applicability in wastewater treatment across diverse pollutant spectra.