Study On Determination Of Propanil And Lead(Ⅱ) By Sequential Injection Analysis Coupled With Chemiluminescence Detection

In this thesis, the sequential injection (SI) technique coupled with chemiluminescence (CL) detection was developed for the determination of Propanil and Pb(Ⅱ) and satisfactory results were obtained.The first section of the thesis introduced the classification of pesticide, the pollution to environment and the harm to human, the detection technique of pesticide residue and the degradation technique of pesticide residues.The second section of the paper dealt with an ananlytical strategy on coupling photodegradation, chemiluminescence and sequential injection methodology for the determination of the pesticide propanil, a common herbicide. The method is based on the direct oxidation of the photoproducts of propanil by potassium permanganate in weak acid medium. The sampling sequence of reagents and sample, the concentration and volume of reagents, the detection flow rate and so on were optimized by univariate method. Under the optimized condition, the linear concentration range was0.01-10mg/L propanil with a correlation coefficient (R) of0.9995and relative standard deviation (RSD) of2.9%(n=11), the detection limit (3σ) was0.009mg/L. The proposed method has been applied to determination of propanil in environmental natural waters and vegetables. The recoveries were in the range of90.7-104.6%.In the third section, a SI-CL method was developed for the determination of Pb(Ⅱ). It was based on the intense chemiluminescence generated by the oxidation-reduction reaction of Luminol and potassium permanganate under the catalysis of Pb(Ⅱ) in alkaline medium. Under the optimized condition, The chemiluminescence intensity was linear with the concentration of Pb(Ⅱ) over the range0.05-2.0mg/L, the detection limit (3σ) was0.009mg/L and the relative standard deviation for eleven repeated measurements for1.0mg/L Pb(Ⅱ) was1.2%, The method was applied to the determination of Pb(Ⅱ) in the environmental sample and the recoveries were over the range90.0-107.7%.In the last section, a summary for content of the experimentation was described.