阴-非离子表面活性剂存在下在DMF介质中用镉试剂2B测定银的研究

Spectrophotometric Determination of Silver with Cadion 2B in DMF and the Presence of Anion-nonionic Surfactant

本文研究了在阴-非离子表面活性剂SDS-TritonX-100存在下,用Cadion 2B分光光度法测定银,发现DMF介质的增溶、增敏、增稳效果均好.配合物的最大吸收波长为560nm,表现摩尔吸光系数为1.23×10~5L·mol^(-1)·cm^(-1),Ag(Ⅰ)在0—18μg/25ml范围内服从比耳定律.该方法操作简便、快速,选择性好,可直接用于废水中微量银的测定,结果满意.

A highly sensitive and selective procedure of spectrophotometric determination of silver has been developed. At pH 9.2, in the presence of Triton X-100-SDS, silver forms a complex with Cadion 28, which has an absorption maximum at 560nm. The molar absorptivity is 1.23×105L-mol-1-cm-1. Beer's law is obeyed for silver in the range 0-18μg/25ml. The colour of aqueous solutions is stable for at least 24 hours. The method has been used to determine silver in waste-water without separation.