土壤中痕量铅(Ⅱ)的偶合反应流动注射化学发光增敏法测定  

Determination of Trace Pb(Ⅱ) in Soil by Increasing Sensitivity Method with Coupling Reaction of Flow Injection/Chemiluminescence

作　　者：高智席[1] 刘焱[1] 黄成[2] 

机构地区：[1]遵义师范学院化学系,贵州遵义563002 [2]西南大学化学化工学院,重庆北碚400715

出　　处：《安徽农业科学》2008年第23期10071-10073,共3页Journal of Anhui Agricultural Sciences

基　　金：贵州省教育厅自然科学青年项目(黔教科2007072)

摘　　要：[目的]建立了测定铅的新方法。[方法]基于Ph（Ⅱ）能置换出Fe（Ⅱ）-EDTA络合物中的Fe（Ⅱ）和鲁米诺-罗丹明B—Fe（Ⅱ）产生化学发光的反应，建立了简易、快速测定土壤中铅的置换偶合反应流动注射化学发光增敏法。[结果]实验建立的优化条件为：鲁米诺溶液和罗丹明B的流速为75r／min，Pb（Ⅱ）和Fe-EDTA的流速为30r／min，混合管L1的长度为150cm，L2的长度为5cm，在pH值为3、0的硝酸介质中Fe（Ⅱ）与EDTA的络合比为1：1，化学发光反应在pH值为10.6，鲁米诺和罗丹明B浓度分别为5．0×10^-5和1.0×10^-5mol／L，负高压为1190V。在优化的实验条件下，铅的线性范围为6．0×10^-9 ～2.8×10^-7mg／L，检出限为2.0×10^-9mg／L。[结论]该法适用于土壤中铅的测定。[ Objective] The study was to establish a new method for the determination of Pb. [ Method] Based on the replacement of Fe （ Ⅱ ） by Pb （ Ⅱ ） from Fe （ Ⅱ ） -EDTA complex, and the chemiluminescence reaction of Fe（ Ⅱ ） -luminol-RhB, the increasing sensitivity method with coupling replacement reaction of flow injection/chemiluminescence was established for simple and quick determination on Pb in soil. [ Result] The optimum conditions established in the experiment were that： the flow rate of lumino solution and RhB were 75 r/min, that of Pb （ Ⅱ ） and Fe-EDTA was 30 r/min, The length of mixing pipe L1 was 150 cm, and that of L2 was 5 cm. The complexation rate of Fe （ Ⅱ ） and EDTA was 1：1 in nitric acid medium with pH of 3.0. During chemiluminescence reaction, its pH value was 10.6, the concn, of luminal and RhB was 5.0 × 10^-5 and 1.0 × 10^-5 mol/L resp. , and the negative high-voltage was 1 190 V. Under the optimum experimental conditions, the linear range of Pb was 6.0 ×10^-9 - 2.8 × 10^-7 mg/L with a detection limit of 2.0 × 10^-9 mg/L. [ Conclusion] The method was suitable to determine Pb （ Ⅱ ） in soil.

关 键 词：流动注射 化学发光 土壤 铅 

分 类 号：S152[农业科学—土壤学]