锌(Ⅱ)-硫氰酸钾-藏红T反应体系分光光度法测定痕量锌  

Spectrophotometric Determination of Trace Amount of Zinc with the Reaction System of Zn(Ⅱ)-Potassium Thiocyanate-Safranine T

作　　者：李人宇[1] 李咏梅[2] 卢洋[1] 周杉杉[1] 

机构地区：[1]连云港师范高等专科学校,连云港222006 [2]淮海工学院化学工程学院,连云港222005

出　　处：《理化检验（化学分册）》2011年第12期1384-1386,1390,共4页Physical Testing and Chemical Analysis(Part B:Chemical Analysis)

基　　金：连云港市社会发展项目;江苏省海洋资源开发研究院科技开放基金项目(JSIMR09C08)资助

摘　　要：在pH 3.6乙酸-乙酸钠缓冲溶液中,在曲拉通X-100存在下,锌(Ⅱ)与硫氰酸钾和藏红T(ST)反应生成稳定的离子缔合物[ST]4[Zn(SCN)6]。离子缔合物的最大吸收波长为482nm,锌(Ⅱ)的质量浓度在0.006～0.70mg.L-1范围内符合比耳定律,表观摩尔吸光率为5.41×104L.mol-1.cm-1。方法用于测定河水中锌,结果与双硫腙光度法一致。以河水样品为基体,用标准加入法做回收试验,测得平均回收率为99.4%,测定值的相对标准偏差(n=5)均小于3.5%。In an acetate buffer medium of pH 3.6,and in the presence of Triton X-100,a stable ion association complex was formed between Zn（Ⅱ）,in the form anionic complex of Zn（SCN）64-,and safranine T（ST＋）,having its empirical formula 4[Zn（SCN）6].The absorption maximum of the ion association complex was found at the wavelength of 482 nm.Lambert-Beer′s law was obeyed in the concentration range of 0.006-0.70 mg·L-1 for Zn（Ⅱ）,with its apparent molar absorptivity of 5.41×104L·mol-1·cm-1.The proposed method was used in the analysis of 2 river water samples for their zinc contents,the results obtained were in consistency with the results found by the dithizone-photometric method.Tests for recovery was made by standard addition method using the river water samples as matrixes,value of average recovery was found to be 99.4% with RSD′s（n=5） less than 3.5%.

关 键 词：分光光度法 锌(Ⅱ) 硫氰酸钾 藏红T 曲拉通X-100 

分 类 号：O657.32[理学—分析化学]