新型螯合物分离阻化动力学光度法测定痕量镉

Catalytic Kinetic Spectrophotometric Determination of Trace Cadmium after Separation and Preconcentration by Pyrrolidine Dithiocarboxylic Acid Ammonium Salt Chelating Cellulose

在碳酸钠介质中,以2,2′ 联吡啶为活化剂,Cd2+对过氧化氢氧化偶氮氯膦Ⅲ褪色反应具有抑制作用。考察了反应动力学条件,建立了一种测量痕量镉的新的动力学光度法。方法的检出限为1.0×10-11g/mL,线性范围为0～2.0μg/10mL。用APDC螯合纤维分离富集后,测定了湖水中痕量镉,并与原子吸收法对照,结果一致。

Cadmium is a kind of heavy mental element and possesses the important significance of environmental inspection. In the medium of sodium carborate, cadmium possesses inhibitory action on the discoloring reaction of hydrogen peroxide oxidating chlorophosphorazo(Ⅲ)with 2,2′-bipyridine as activating agent. Based on the above fact, a new catalytic kinetic spectrophotometric method was proposed for the determination of trace cadmium. The detection limit of this method is 1.0×10^(-11) g/mL, and the linear dynamic range varies from 0 to 2.0 μg/10mL.Combined with APDC chelated cotton cellulose separation and enrichment, the proposed method was applied to the determination of trace cadmium in lake water with satisfactory results.