取代苯酚臭氧氧化表观速率常数的QSPR研究

在298 K,1.013×105 Pa条件下,对22种取代苯酚在水溶液中的臭氧降解过程的动力学进行了实验研究,采用紫外分光光度法测定了降解过程中取代苯酚的浓度,并求得反应级数和反应表观速率常数。使用Gaussian 98程序中B3LYP6-311G**方法,计算了取代苯酚的结构参数及热力学参数,并采用QSPR方法研究了表观速率常数与其结构及热力学参数之间的关系。研究结果表明:取代苯酚的臭氧氧化反应属0级反应,表观速率常数与其结构和热力学参数之间存在线性关系,相关方程的相关系数R2=0.978,标准误差SD=0.050,分子的极化率是影响表观速率常数的主要因素。

Determination and QSPR Study of Ozonation Apparent Reaction Rate Constant of Substituted Phenols

Ozonation kinetics of 22 substituted phenols in aqueous solution were investigated at 298K and 1.013×105Pa.Concentrations of substituted phenols were detected by ultraviolet spectrophotometry during ozonation process to calculate reaction orders and apparent reaction rate constants.Optimized calculations of substituted phenols were carried out at B3LYP/6-311G** level with Gaussian 98 program and structural and thermodynamic parameters were obtained from optimized calculations.Relationship between apparent reaction rate constant and structural and thermodynamic parameters was also investigated by quantitative structure-property relationship method.Results showed that reaction order was zero,with apparent reaction constants and calculated parameters in good linear relationship.Optimized equation showed polarizability of a molecule had significant effect.