阿维菌素在水溶液中的光化学降解

目的]研究阿维菌素在不同光源下的光解动力学。【方法]以高压汞灯为光源，研究了不同初始浓度、pH值、共存污染物等因素对阿维菌素光化学降解的影响。结果]阿维菌素在紫外灯下的光解速率是高压汞灯下的数倍，其半衰期在高压汞灯下为25．6min，在紫外灯下仅为4．9min。阿维菌素的最大吸收峰在245nm。在试验的初始浓度范围内，阿维菌素的光解反应符合一级反应动力学规律，阿维菌素的光解速率与其初始浓度呈负相关。pH值为4时，阿维菌素的光解半衰期为29．9min，pH值为9时，则缩短到了24．8min。NO3-、甲基绿、甲基橙、十二烷基磺酸钠对阿维菌素的光解速率均表现出一定的光猝灭作用。添加甲基橙后，阿维菌素的光解半衰期比对照延长了7．4min，添加甲基绿后延长了9．3min。结论]该试验初步研究了阿维菌素在水溶液中的光解过程及其影响因素。

Photochemical Degradation of Avermectin in Aqueous Solution

Objective] The aim was to research the photolysis kinetics of avermectin under different light sources.Method] With high-pressure mercury lamp as light source,the influences of factors including different initial concn.,pH and co-existing pollutants on the photochemical degradation of avermectin were researched.Result] The photolytic rate of avermectin under UV lamp was several times of that under high-pressure mercury lamp;its half-life was 25.6 min under high-pressure mercury lamp and only 4.9 min unde...