Degradation of Atrazine in Soil Through Induced Photocatalytic Processes

We observed photocatalytic degradation of atrazine in the presence of semiconductor metal oxide particulates (TiO2, ZnO) suspended in aqueous solution under simulated sunlight irradiation. The half-life for the process is ca. 5 and 80 min for TiO2 and ZnO, respectively (at an initial atrazine concentration of 25 mg/liter with 0.5 g of semiconductor per liter and with a photon flux of 3 x 10-5 einstein/min, and over a cell cross section of 4 cm2). We investigated the catalytic activity of different soils. The weak photocatalytic activity of the soils (2 g/liter) is dramatically increased by the addition of 0.5 g of the semiconductor per liter. Half-lives are 10 to 40 minutes, depending on the nature of the soil.