用分光光度法测定痕量铜、锌离子

Determination of Trace Copper and Zinc by Spectrophotometry

研究了用PAN螯合剂负载的聚氨酯泡沫塑料富集铜、锌离子,用分光光度法测定其痕量的简单易行方法。12吡啶偶氮1萘酚(PAN)在pH9.0缓冲液中既做为负载剂又做为显色剂。铜、锌离子富集之后用1 mol/L硝酸洗脱,用光度法测定。铜、锌离子均在0～12μg/10ml范围符合比尔定律。最大吸收波长为555nm,摩尔吸光系数5.36×10~4L·mol^(-1)·cm^(-1)。本法可用于天然水和麦饭石水中铜、锌离子含量的测定。

The polyurethane foamed plastics is enriched with Zn and Cu in water and loaded with 1 -(-1 -pyridylazo-)-1-naphthol (PAN) chelating agents. Then the trace copper and zinc in natural water and water of medical stone was determinated by spectrophotometry, pAN is used as loaded and chromonophoric reagent is in the PH=9.0 buffer solution. After enrichement it is eluted with 1 mol/L HNO_3 solution and determinated with spectrophotometry. Beer's law is obeyed in the range of 0～12μg/10ml for copper and zinc, wavelength of maxmum absorption is in 555nm. The molar absorptivities are about ε_(555)^(Cu^(2+))=4.67×10~4L.mol^(-1).cm^(-1), ε_(555)^(Zn^(2+))= 5.37×10~4L·mol^(-1)·cm^(-1).