高铁酸钾降解苯并[a]芘的偏振三维荧光(PEEM)研究

Research on Degradation of Benz[a]pyrene by Potassium Ferrate Using Fluorescence Polarization Excitation Emission Matrix(PEEM)

偏振三维荧光(PEEM)结合了偏振技术和三维荧光(EEM)的优点,对于完整获取分子荧光特性能提供重要信息,具有更高的选择性、准确性及灵敏度。运用PEEM进一步探讨了高铁酸钾对苯并[a]芘的降解过程,并分别从该降解体系反应过程中的偏振度和PEEM特征变化,深入揭示了高铁酸钾对苯并[a]芘的降解规律.结果显示,t=15s,苯并[a]芘的降解率约60%,t=40s,降解率达90%.偏振度(P)更清晰反映了苯并[a]芘的难降解特性.通过对高铁酸钾-苯并[a]芘体系降解的时间偏振曲线拟合,获得了一级反应动力学方程:y=0.277x-0.004(r=-93.90%)。以上研究结果与前期研究中应用EEM所获得的结果一致,为研究高铁酸钾降解其他污染物反应过程,机理提供了十分有益的方法选择的参考。

Polarized excitation emission matrix（PEEM）, combining advantages from both polarized technology and excitation emission matrix （EEM）, is a analytical tool with higher selection, accuracy and sensitivity, which could provide complete information for molecular characterization. The degradation of benz[a]pyrene by potassium ferrate was further studied by PEEM in this paper, and the degradation features were also deeply discussed through polarized values and PEEM changing. According to the experiment, for t=15 s, the degradation rate was 60~ while for t=40 s, above 90~. Polarized value characterized more clearly the difficult degradation of benz[a] pyrene. The first order kinetic equation also obtained： y = 0. 277x -- 0. 004 （ r = -93.90%）, by fitting the time polarized curve. These results are accord with the psevious results obtained from EEM＇s characterization, which provide a very useful conference for method selectivity in researching process and mechanism of pollutants degradation.