1967 年 16 巻 10 号 p. 1071-1073
Traces of copper in lead metal were determined by chloroform extraction and bathocuproine photometric method. The procedure has been established as follows. Lead metal samples are dissolved in nitric acid and the sample solutions (Cu 115 μg) are transferred to separatory funnels and later diluted to about 60 ml. Then 5 ml of ammonium acetate (30%) and 1 ml of hydroxylamine hydrochloride (10%) are added. The pH of these solutions are adjusted at 3.55 with ammonium hydroxide. Two ml of 0.1 % bathocuproine alcohol solution is added and then it is kept standing for 5 minutes. The solution was shaken with 5 ml of chloroform for 3 minutes. The absorbance of copperbathocuproine complexs extracted is measured at 477 mμ, and the copper content is determined by reference to the calibration curve.
According to this method any seperatory procedure from other elements in lead metal is unnecessary in advance. Therefore, it is recommended to be a simple. and rapid procedure for the analysis.