硫酸介质中高锰酸钾氧化降解非离子表面活性剂Tween-80动力学研究

KINETICS OF OXIDATIVE DEGRADATION OF NONIONIC SURFACTANT TWEEN-80 BY KMnO4 IN H2SO4 MEDIUM

应用光谱法研究了硫酸介质中,高锰酸钾氧化降解非离子表面活性剂Tween-80(聚氧乙烯山梨糖醇酐单油酸酯)的动力学性质,探讨了高锰酸钾和硫酸浓度,以及反应温度对氧化降解过程的影响,结果表明,氧化降解反应的速率常数(k)随着硫酸浓度的增大而增大,但却随着高锰酸钾浓度的增大而减小;温度对反应速率常数的影响,较好地遵循阿累尼乌斯公式.通过对反应混合物浊点变化的分析,说明了非离子表面活性剂Tween-80分子中存在活性较高的氧乙烯结构单元,是其被高锰酸钾氧化降解的根本原因.

Reaction kinetics of oxidative degradation of Tween-80 by KMnO4 in H2 SO4 medium was investigated by UV-Vis spectrum method. The effect of H2 SO4 and KMnO4 concentration, and reaction temperature on oxidative degradation was explored. The results show the rate constant of oxidative degradation increased with H2SO4 concentration, but decreased with KMnO4 concentration. The influence of temperature on the rate constant of oxidative degradation can be fitted with Arrhenius equation. According to the change of point of reaction mixture, the presence of oxyethylene structural unit in Tween-80 skeleton is respo the degradation of polyoxyethylene chains.