王水回流溶样–火焰原子吸收光谱法测定地质样品中的金

Determination of gold in geological samples by flame atomic absorption spectrometry with reflux solution digestion by aqua regia

建立王水回流溶样聚氨酯泡沫塑料吸附火焰原子吸收光谱法测定地质样品中金的分析方法。在传统法使用锥形瓶王水溶样的基础上,在磨口锥形瓶上增加回流装置,以长15cm的玻璃管作为冷却回流管,加入30mL王水溶液(1+1)对样品进行消解,采用火焰原子吸收光谱法测定。金的质量浓度在0~4.00μg/mL范围内与吸光度呈良好的线性关系,相关系数为0.9993,检出限为0.058μg/mL。金矿石标准物质测定结果的相对标准偏差为2.75~6.41%(n=6),相对误差为–5.00%~0.61%;5种不同矿区金矿石样品测定结果的相对标准偏差为2.02%~9.24%(n=9)。该方法样品消解完全,减少了王水的使用量和氮氧化物的排放,操作简便,结果准确可靠,适用于地质样品的批量分析。

A method for the determination of gold in geological samples by flame atomic absorption spectrometry with polyurethane foam adsorbed by aqua regia reflux solution was established. Based on the traditional use of aqua regia sample in conical bottle,a reflux device was added to the conical bottle with grinding mouth. The sample was digested by adding 30 mL aqua regia solution (1+1) with the glass tube for 15 cm long as cooling reflux tube. The mass concentration of gold had good linear relationship with the absorbance in the range of 0–4.00 μg/mL. The correlation coefficient was 0.999 3 and the detection limit was 0.058 μg/mL. The relative standard deviation of the determination results of gold ore reference materials was 2.75%–6.41%(n=6),and the relative error was-5.00%–0.61%. The relative standard deviation of the determination results of gold ore samples from five different mining areas was 2.02%–9.24%(n=9). The sample can be dissolved by this method and the consumption of aqua regia and the emission of nitrogen oxides were reduced. The method is simple,accurate and reliable. It is suitable for batch analysis of geological samples.