Photocatalytic degradation of diesel pollutants in seawater under visible light

Photocatalyst composites were prepared by coprecipitation and characterized by XRD, SEM, and UV-Vis DRS methods. A substantially enhanced photocatalyst activity was observed in degradation of diesel pollutants in seawater, compared to zinc oxide without dopant. Photocatalytic degradation of diesel pollutants in seawater and the effects of factors on the composite's photocatalytic effectiveness were studied under visible light and various conditions. This degradation in seawater was optimized using an orthogonal experimental plan. According to the results, diesel removal was 26.95% without any catalyst (losses only by evaporation) and the greatest effects occurred when the initial diesel concentration was 0.25 g/L, catalyst dose at 0.4 g/L, catalyst-doping ratio at 10%, pH at 9.0, H2O2 at 6.0 mg/L, and illumination time at 2.5 h, in which case the diesel removal rate reached 93.89%. This study elaborated a means for making zinc oxide utilize visible light more efficiently and thus accelerate the practical application of photocatalytic technology in organic pollutant remediation.