敌草快的水解动力学研究

研究了敌草快于25℃下在去离子水、河水和地下水3种水体不同pH值(pH 5、7、9)条件下的水解动力学以及pH为9时不同温度(10、25、35℃)条件下的水解行为。结果表明,敌草快的水解动力学属于一级反应,且其在去离子水中的水解速率与其在河水和地下水中的相似;敌草快在酸性和中性条件下比较稳定,不易水解,而在碱性条件下水解较快;温度升高有利于水解反应,水解活化能为25.89 kJ/mol,活化熵为-191.81 J/mol·K,温度效应系数为1.52。

Hydrolysis Dynamics of Diquat in Aquatic Environment

The hydrolysis dynamics of diquat in deionized water,river water and ground water were studied by incubation at 25℃ and the hydrolysis dynamics of diquat at different temperature(10℃,25℃,35℃) in pH 9 were investigated.The degradation was followed by GC.The experimental results indicated that the kinetic process of diquat can be described by the first-order reaction,the hydrolysis rates of diquat in deionized water,river water and ground water were almost the same.The pH was a critical factor of the rate of the degradation of diquat in aqueous solutions.Diquat was stable in acid water and neutral water,but its hydrolysis easily took place in basic water.The higher temperature was helpful for the hydrolysis during the range from 283 K to 308 K in basic water,the activation energy of hydrolysis for diquat was 25.89 kJ/mol,activation entropy was -191.81 J/mol·K,and the temperature coefficient was 1.52.