Performance assessment of PbO in UV assisted photocatalytic degradation of Remazol Brilliant Green dye

Remazol Brilliant Green (RBG) is a toxic and persistent dye widely used in the textile industry, posing severe environmental and health hazards due to its stability and resistance to conventional treatment methods. This study investigates the photocatalytic degradation of RBG using lead oxide (PbO) as a novel photocatalyst under UV irradiation. The novelty of this work lies in the application of PbO, which exhibits superior photon absorption, efficient charge carrier separation, and enhanced oxidative activity compared with traditional catalysts such as TiO2 and ZnO. The influence of pH, catalyst dosage, and initial dye concentration on degradation efficiency was systematically examined. Under optimal conditions of pH 8, 2.5 g/L PbO, and 5 mg/100 mL dye concentration, the degradation reached 97%. The chemical oxygen demand (COD) decreased from 320 to 10 mg/L, and the CO2 concentration increased from 0 to 290 mg/L, confirming complete mineralization of the dye. The degradation efficiency dropped from 97% to 68.6% in the presence of EDTA-2Na, indicating the involvement of reactive species in the degradation mechanism. PbO retained high photocatalytic activity after multiple reuse cycles, demonstrating its stability and potential as a sustainable photocatalyst for effective treatment of industrial dye-contaminated wastewater.