Dynamics and mechanism of ultraviolet photolysis of atrazine on soil surface

The photolysis of atrazine in the soil surface under UV light and the factors affecting this has been studied. A rate constant of 0.09-0.17 min(-1), photolytic depth of 0.1-0.3 mm and half-life of 4-8 min were determined. The results show that soil granularity, pH, humidity, organic content, humic acid and surface-active agents could affect the photolysis of atrazine in soil. GC-MS showed three photolytic products: 1-sec-butyl-4,1-diethyl-1-tetrazene, N-2,N-4-diethyl-6-methyl-1,3,5-triazine-2,4-diamine and 6-chloro-N-2-propyl-1,3,5-triazine-2,4-diamine. The mechanism of the photolytic process is discussed. (C) 2001 Society of Chemical Industry.