树脂D301M吸附草甘膦的热力学及动力学

Adsorbing Thermodynamics and Kinetics of Resin D301M to Glyphosate Solution

通过静态吸附实验,研究了树脂D301M对草甘膦水溶液的吸附热力学和吸附动力学特性.测定了303.15～318.15K的等温吸附线和吸附动力学数据,并分别用Langmuir,Freundlich,Temkin模型拟合了树脂D301M吸附草甘膦水溶液的实验数据.结果表明,树脂D301M对水溶液中草甘膦的吸附符合Langmuir等温吸附方程,并根据热力学原理,计算出吸附热力学参数,其吸附焓值ΔH=58.42kJ.mol-1,ΔG>0,ΔS>0.树脂D301M的吸附过程符合准二阶动力学方程;采用Arrhenius方程计算出吸附的表观活化能Ea=165.22kJ.mol-1.

The adsorbing kinetics and thermodynamics of resin D301M to glyphosate solution were investigated by implementation of state adsorption experiments. The adsorption isotherm and kinetics in the range from 303.15 to 318.15 K were determined. Langmuir, Freundlich, and Temkin isotherm equations were employed to describe the adsorption process and fit the experimental data. The results indicate that the Langmuir isotherm function fits the data better. The parameters of adsorbing thermodynamic, AH, AG and AS were calculated. The kinetics of the resin D301M adsorbing process follows a pseudo-second-order model. It is found that, under low temperature, the diffusion of liquid sheet and chemical reaction are the dominant procedure, but, with the temperature increasing, the ion particle diffusion becomes the dominant procedure gradually. According to the Arrhenius equation, the calculated apparent activation energy is 165.22 kJ·mo1-1.