Highly efficient kaolin/g-C3N4/WO3 ternary nanocomposite for the effective removal of Arsenic ions from aqueous media

Abstract

The effectual removal of arsenic ions from contaminated water sources remains a significant challenge in water treatment. In this study, we propose a novel composite material consisting of kaolin, graphitic carbon nitride (g-C3N4) and tungsten trioxide (WO3) for effective arsenic removal. The composite material was prepared through a facile synthesis method, and its physicochemical properties were characterized using various analytical techniques. The effects of composite dosage, initial arsenic concentration, contact time and temperature on the adsorption capacity were systematically evaluated. The results revealed that the composite material exhibited excellent arsenic removal efficiency, with a maximum adsorption capacity of 114.63 mg/g. The adsorption isotherms such as Langmuir and Freundlich models were evaluated, and the data finds to fit well with the Langmuir model, suggesting homogeneous adsorption. The mechanism of arsenic removal follows photocatalytic oxidation of As(III) to As(V) followed by adsorption of As(V). The process of adsorption followed the pseudo-second-order kinetic model. Additionally, the composite material demonstrated good reusability and stability over multiple cycles. The findings of this study contribute to the progress of sustainable and reliable water treatment technologies for arsenic removal, addressing a pressing global environmental concern.