【摘要】 在初始pH7.0的Fe(Ⅱ)/K2S2O8体系中,分别研究了K2S2O8和Fe(Ⅱ)初始浓度以及Fe(Ⅱ)分批加入对敌草隆降解的影响,结果表明,在pH 7.0,K2S2O8和Fe(Ⅱ)初始浓度分别为2.0mmol.l-1和1.0mmol.l-1时,反应300min后,0.1mmol.l-1敌草隆的降解率达到40.0%,Fe(Ⅱ)分批加入能够促进敌草隆的降解.另外,通过对Fe(Ⅱ)/K2S2O8,EDTA-Fe(Ⅱ)/K2S2O8,柠檬酸-Fe(Ⅱ)/K2S2O8以及K2S2O3-Fe(Ⅱ)/K2S2O8四种Fe(Ⅱ)/K2S2O8体系的对比研究,发现在Fe(Ⅱ)/K2S2O8体系中,加入Fe(Ⅱ)的螯合剂EDTA和柠檬酸以及还原剂K2S2O3能够明显促进敌草隆降解.采用分子探针法的竞争实验鉴定了体系中产生的硫酸根自由基.更多还原

【Abstract】 The degradation of Diuron(3-(3,4-dichlorophenyl)-1,1-dimethylurea) in aqueous solution system by persulfate oxidation activated by ferrous ion was conducted,as well as the influence of individual initial concentration of K2S2O8,Fe(Ⅱ) and sequential addition of Fe(Ⅱ).At initial pH value of 7.0,when the dosage of K2S2O8 and Fe(Ⅱ) were 2.0mmol·l-1 and 1.0mmol·l-1,degradation ratio of 0.1mmol·l-1 Diuron was observed as 40.0% after 300min reaction,and sequential addition of Fe(Ⅱ)resulted in an increased Diuron degradation.In addition,compared EDTA-Fe(Ⅱ)/K2S2O8,citric acid-Fe(Ⅱ)/K2S2O8 and K2S2O3-Fe(Ⅱ)/K2S2O8 with Fe(Ⅱ)/K2S2O8,Diuron degradation was increased when the addition of chelating agents(i.e.,EDTA and citric acid) and reducing agent(i.e.,thiosulfate).Sulfate radicals produced in the system were determined by molecular probes(ethanol and tert-butanol)methods.更多还原