Photocatalytic degradation of geosmin by Pd nanoparticle modified WO3 catalyst under simulated solar light

Abstract

Geosmin (GSM), a typical musty odor compound, causes undesirable earthy off-flavors and is a serious concern in the drinking water and aquaculture industries. Here, we employed a novel palladium (Pd) modified tungsten trioxide (WO3) photocatalyst to remove GSM from water under simulated solar light. We also investigated the effect of catalyst loading, GSM initial concentration, light intensity, pH and dissolved oxygen (DO) for GSM destruction. The Pd/WO3 catalyst almost completely degraded GSM within 20min under optimum conditions, with GSM degradation conforming to a pseudo-first-order reaction. This catalyst also exhibited a superior reuse performance. Photocatalytic degradation rate of GSM decreased in the presence of hydroxyl radical trapping reagent, implying oxidation by hydroxyl radicals plays a very significant role in the photo-degradation mechanism. Some possible intermediates were also identified. These results could provide helpful information for constructing a new efficient system for rapid GSM removal under solar light.