Photocatalytic activity of synthetic ZnO/WO3 nanocomposites immobilized on a Y-zeolite in removal of gas-phase styrene.

Abstract

The widespread use of styrene along with its harmful effects on human health has led to many studies on how to control and reduce its vapors in the workplace. In this study, efficient removal of styrene molecules in the gas phase was attempted by using Y-ZnO/WO3 hybrid photocatalysts. ZnO/WO3 nanocomposites with different WO3 Wt% were prepared and immobilized on Y-zeolite. The samples' characteristics were evaluated using X-ray diffraction (XRD), energy dispersive X-ray spectrum (EDS), Brunauer-Emmet-Teller (BET) and field emission scanning electron microscopy (FESEM). The Y- ZnO/WO3 catalyst exhibits an improved photocatalytic activity as compared to Y-ZnO and Y-zeolite alone. This higher photocatalytic activity of the ZnO/WO3 supported on Y-zeolite can be attributed to a more efficient interaction of the ZnO/WO3 with the zeolite leading to higher adsorption capacities. Results reveal that the photocatalyst was highly photoactive in mineralizing styrene. The high activity can be attributed to the synergetic effects of strong UV, ZnO/WO3 nanocomposite and surface hydroxyl groups. The photocatalytic degradation reaction of styrene with the Y-ZnO/WO3 follows Langmuir-Hinshelwood kinetics. The results of this study indicate that this photocatalyst is suitable for the removal of styrene under UV light. The highest removal efficiency achieved was with Y-ZnO/WO3 at 2%.