氯代磺酚S光吸收比差法测定环境水体中痕量铜

在pH4.05的醋酸-醋酸钠溶液中, 显色剂氯代磺酚S（CSPS）与Cu(Ⅱ)反应形成Cu-CSPS络合物, 用光谱修正法表征其结构为［Cu₂(CSPS)₂(H₂O)₂］^2-, 利用此反应结合光吸收比差法建立了Cu(Ⅱ)定量分析新方法。研究表明, 显色剂溶液性质稳定, 在适量F^-掩蔽剂存在的条件下, 测定0.050mg/LCu(Ⅱ), 500倍的Ca²⁺, 250倍Mg²⁺, 5倍Mn²⁺、Ni²⁺、Cl^-、NO^2-、PO₄^3-以及与Cu²⁺同倍的Zn²⁺、Co²⁺、Pb²⁺、Cd²⁺、Cr(Ⅲ)、As(Ⅲ)、Fe(Ⅱ)、Fe(Ⅲ)、Al(Ⅲ)不影响测定。Cu(Ⅱ)的检出限为1.35μg/L。方法用于两个天然水样中痕量铜的测定, 结果与ICP-AES法的结果相吻合, 相对标准偏差分别为1.4%和2.6%（n=7）。

Determination of trace copper in environmental water by lightabsorption ratio variation approach with chlorosulphonphenol S

In the acetic acid sodium acetate solution of pH 4.05, chromogenic reagent chlorosulphophenol S (CSPS) reacted with Cu(Ⅱ) to form a CuCSPS complex. The spectral correction indicated its structure was Cu2(CSPS)2(H2O)2］^2-. By combining this method with absorbance ratio difference method, a novel method for the quantitative analysis of Cu(Ⅱ) was established. Research indicated that the chromogenic reagent solution was stable. With the existence of an appropriate amount of F^- masking agent, 500 times of Ca²⁺, 250 times of Mg²⁺, 5 times of Mn²⁺, Ni²⁺, Cl^-, NO2^-, PO4^3- and the equivalent amount of Zn²⁺, Co²⁺, Pb²⁺, Cd²⁺, Cr (Ⅲ), As(Ⅲ), Fe(Ⅱ), Fe(Ⅲ) and Al(Ⅲ) did not influence the determination of 0.050 mg/L Cu(Ⅲ). The detection limit of Cu (Ⅱ) was 1.35 μg/L. The method was used for determining trace copper of two natural water samples, with results compared with those obtained by ICPAES and RSD of 1.4% and 2.6% respectively (n=7).