H_2O_2清洗对蔬菜中农药去除效果及机制的研究

为了提高蔬菜在清洗过程中的农药去除率,利用低浓度的H_2O_2清洗不同类型的蔬菜。结果表明,在酸性(p H=4.0)条件下,含铁量较高的蔬菜能较明显提高H_2O_2氧化去除敌敌畏的效率。通过叔丁醇试验发现,敌敌畏去除率的提高主要原因可能是由于蔬菜基质自身的Fe~(2+)或Fe~(3+)催化H_2O_2有效地产生了高活性的羟基自由基。试验进一步探讨了H_2O_2清洗几种典型的有机磷、有机氯和氨基甲酸酯类农药的降解,结果表明该体系针对不同类型的农药都具有降解效率。

Study on Removing Pesticide Residues and Mechanism from Vegetable by H2O2 Rinsing

In order to promote the removal rate of pesticides on vegetables in the cleaning process, the degradation of pesti-cide by hydrogen peroxide (H2O2) for different vegetables were studied. The results showed that vegetables which contained larger amount of iron could obviously improve the oxidation efficiency of the catalytic H2O2 process for dichlorvos degradation under pH 4.0. The tert-butyl alcohol addition tests indicated that the improvement of dichlorvos degradation was owing to generation of highly active hydroxyl radicals in the iron ion (in vegetables) catalytic H2O2 process. Further study about the degradation of several typical pesticidessuch asorganophosphorus,organochlorine and carbamaterevealed that the proposed pro-cesshad highly activity in degrading different kind of pesticides.