测定粗铜中痕量金的重量法费时费力,参照前人的经验,本文提出蜡浸石墨电极示波极谱法;以饱和甘汞电极为参比,0.5MHCl为基底溶液,在恒速搅动试液下制取金的伏安曲线,其峰电位为+0.28±0.4伏,峰电流在Au(Ⅲ)为0.2至10微克/毫升范围线性关系良好,Bi~(3+)、Pb~(2+)、Zn~(2+)、Ni~(2+)达200倍量对测定无影响,Cu~(2+)20倍量以上使金的伏安曲线歪曲;方法应用于测定粗铜中金时,铜的干扰可在1:4HCl介质中以甲基异丁基酮(MIBK)萃取金而消除,用双标准比较法定量,测量误差均在±10％以内。 (一)仪器和试剂示波极谱仪;JP-1A型。蜡浸石墨电极:将上海碳素厂生产的6×30毫米光谱纯石墨棒切成7—8厘米长置入熔融石蜡中减压下浸渍,外壁涂 Determination of crude copper in the gravimetric method of time-consuming and laborious, with reference to previous experience, this paper proposed wax-impregnated graphite electrode oscillopolarography; saturated calomel electrode as a reference, 0.5MHCl-based solution at constant speed agitation The voltammetric curve of gold was prepared under the test solution with a peak potential of +0.28 ± 0.4 volt and a peak current of 0.2 ~ 10 μg / ml Au (Ⅲ). The peak current of Bi ~ (3 +), Pb ~ ( 2 +), Zn ~ (2 +) and Ni ~ (2+) up to 200 times the amount of Cu 2+ did not affect the determination. The voltammograms of gold were distorted more than 20 times that of Cu 2+. In the case of gold, the interference of copper can be eliminated by extracting the gold with methyl isobutyl ketone (MIBK) in 1: 4 HCl medium, and the quantification by double standard comparison method is within ± 10%. (A) Instruments and reagents oscilloscope polarography; JP-1A type. Wax leaching graphite electrode: The carbonaceous plant in Shanghai 6 × 30 mm spectrum of pure graphite rod cut into 7-8 cm long placed in molten paraffin under pressure impregnation, the outer wall