Study on volatilization kinetics of parathion-methyl on interphase of the water and air
甲基对硫磷在水-气界面挥发的动力学研究

The influence of volatilization time, temperature and air flux rate on the volatilization behavior of parathion-methyl on the interphase of water and air was investigated. The volatile quantity of parathion-methyl was determined by gas chromatography. The qualitative analysis was made on the basis of retention time, and the quantitative analysis was performed according to the external standard method. The results demonstrated that the increase of temperature and air flux rate could accelerate the volatilization quantity of parathion-methyl largely which suggested that temperature and air flux rate are main factors affecting the volatilization behavior of parathion-methyl. In a certain range of time, for example from the beginning time up to 8 hours, volatilization rate of parathion-methyl was relatively high, after that, the volatilization rate tended to be constant when the air flux rate was 1.5L·min-1 and the concentration of the parathion-methyl solution was 15mg·L-1. The volatilization kinetic model of parathion-methyl has been established. compared the experimental data with the predicted data by the volatilization kinetic model, it can be seen that the experimental results agreed with the prediction basically. Their relative error between the experimental value and predicted value was less than 5%. So the kinetic model can be used well to predict the volatilization behavior of parathion-methyl on the interphase of water and air.