微波消解-电感耦合等离子体原子发射光谱法测定3D硬金饰品中铅、砷、汞、镉的含量

Determination of Lead,Arsenic,Mercury,Cadmium in 3D Hard Gold Jewelry by ICP-AES with Microwave Digestion

取硬金样品约0.1g,加入新配制的盐酸-硝酸(3+1)混合酸6mL,按消解程序进行微波消解。待消解结束后将溶液于80℃加热赶去氮氧化物,冷却至室温后用水定容至50mL,用电感耦合等离子体原子发射光谱法测定其中铅、砷、汞、镉的含量。各元素的质量浓度均在0.10～10.0mg·L^(-1)内与对应的发射强度呈线性关系,检出限(3s)为2.0～8.0mg·kg^(-1)。加标回收率为91.0%～103%。应用该方法分析了21批次3D硬金饰品,测定结果与电感耦合等离子体质谱法的一致,测定值的相对标准偏差(n=6)小于3.0%。

The sample (about 0.1 g) was added into 6 mL of a mixture of hydrochloric acid and nirtic acid (3+1) for microwave digestion according to digestion program. After the digestion was completed, the solution was heated at 80 ℃ to remove nitrogen oxide, cooled to room temperature, and made up to 50 mL with water. The contents of lead, arsenic, mercury and cadmium in the solution was determined by inductively coupled plasma atomic emission spectrometry. Linear relationships were found between emission intensity and mass concentration of the 4 elements in the same range of 0.10^-10.0 mg·L-1, with detection limits (3s) in the range of 2.0-8.0 mg·kg-1. Values of recovery obtained by standard addition method were in the range of 91.0%-103%. The proposed method was applied to determination of the 4 elements in 21 batches of hard gold jewelry samples, giving results in consistency with those obtained by inductively coupled plasma mass spectrometry, and RSDs (n=6) were less than 3.0%.