The degradation of organophosphorus pesticides by hydrogen peroxide I. Characters and influencing factors of the degradation

The characters and influencing factors of the degredation of organophosphorus pesticides of methamidophos, chlorpyrifos and monocrotophos by hydrogen peroxide (H_2O_2) were studied. The result showed that hydrogen peroxide had highly activity in degrading the organophosphorus pesticides, and the degradation rates were 5-13 times of that of the treatment without H_2O_2.Ultraviolet radiation could significantly increase the degradation of the pesticides, which were 3-9 times of the treatment with daylight, and 10-20 times of the treatment without light. When the initial pH-value was at 4-6,the lest degradation rates were gotten, while the rates increased with high basic condition. However, the degradation was restrained with the use of O_2. The degradation rates increased with the time of reaction. The degradation of pesticides was expected to get even better results at higher concentration of H_2O_2 concentration, and the degradation rates was decreased with more chemical added, however, the degraded amount increased.