吸附尾液中痕量金的分光光度测定

SPECTROPHOTOMETRIC DETERMINATION OF TRACE AMOUNT OF GOLD IN EFFLUENTS

研究拟定了吸附尾液中痕量金的测定方法。方法基于用HNO_3-KCIO_3混合液快速有效地破坏金氰络合物,使之转化为Au(Ⅲ);在硝酸介质中用小型高效的CL-5209萃淋树脂柱选择性地吸附Au(Ⅲ),并分离除去大量杂质离子;含金的亚硫酸钠解吸液在10ml比色管中用异戊醇和TMK溶液进行萃取,小心取出有机相,测定其吸光度。方法灵敏度高,样品中金的分析下限可低至0.01mg/L。本方法精密度为±15％,金的回收率为85—107％。

A simple, sensitive and reliable method has been developed for the determination of trace amount of gold in effluents. The method was as folllows: the aurocyanide complex was destroyed by heating with HNO3-KC1O3 solution and turned into Au(IU) rapidly and effectively. In 3. 5% HNO3 medium, the Au(III) was selectively adsorbed on the miniature column (i. d. 0. 6cm) with CL-5209 extractant-containing resin and a great quantity of impurity ions were removed. The sodium sulphite eluate containing gold was extracted with isoamyl alcohol and TMK solution in a 10ml color tube and then the ab-sorbance (in 0. 5cm cell) of organic phase was measured at 540 nm. And a linear calibration graph was obtained for gold concentration in organic phase from 0. 05 to 1. 0mg/1. The method has many advantages- 1. the amount of sample necessary for this method is very small (about 5ml); 2. the determination only needs small volume of organic phase (about 0. 6ml) under the optimal operation conditions;3. the apparatus used is very simple and available (e. g. , the model 72 spectrophotometer) ;4. the procedure is suitable for treatment of the sample solutions containing high concentration of impurities (Ag,Pb, Zn)and trace gold. The determination limit for sample is 0. 01mg/1. The determination of a series of sample solutions can be completed in 3 to 4 hours. The relative standard deviation (N = 6) of the method is better than +15%. The recovery of gold is 85-107%.