乙酸丁酯萃取—火焰原子吸收光谱法测定矿石中痕量金

Determination of trace gold in ores by butyl acetate extraction and flame atomic absorption spectrometry

以乙酸丁酯为萃取剂,建立了火焰原子吸收光谱法测定矿石中痕量金的方法,讨论了矿石的灼烧温度,萃取溶液中溴化钾加入量和王水的浓度等因素的影响。结果表明,其适宜条件为控制灼烧温度为700℃,萃取溶液中溴化钾溶液（100 g/L）加入量为3.0 mL和王水浓度为20%（V/V）。方法检出限为0.03μg/mL。本法用于矿石中金的测定,相对标准偏差≤6.5%,回收率在99%-101%之间。

A determination method of trace gold in ores by flame atomic absorption spectrometry was established with butyl acetate as extracting agent.The influenceing factors were discussed,including the ignition temperature of ores,the addition amount of potassium bromide into extraction solution and the concentration of aqua regia.The results showed that the proper conditions were as follows： the ignition temperature of ore was 700 ℃,3.0 mL of potassium bromide（100 g/L） was added into extraction solution and the concentration of aqua regia was 20 %（V/V）.Detection limit of this method was 0.03 μg/mL.The proposed method has been applied to the determination of gold in ores with relative standard deviation（RSD） less than 6.9 % and recoveries of 99%-101%.