GFAAS和ICP-MS测定化探样品中的痕量金

Determination of trace gold in geochemical samples by GFAAS and ICP- MS

化探样品经650℃高温灼烧、王水(1+1)分解后,在铁盐作用下,用经过酸处理后的聚氨酯泡沫塑料振荡吸附样品溶液中痕量金,以硫脲溶液解脱,待样品溶液冷却后分别用石墨炉原子吸收光谱法和电感耦合等离子体质谱法进行测定。两种方法的检出限、准确度、精密度无显著差异,相对于石墨炉原子吸收光谱法,电感耦合等离子体质谱法的校准曲线线性范围宽、重现性好、测试速度快,缩短了化探样品测试周期,值得推广。

Geochemical samples were pretreated at 650 ℃ and decomposed with aqua regia （ 1 ＋ 1 ）, and under the effect of iron salts, Au in the sample solution was adsorbed with vibration by polyurethane foam plastic that was treated by acids, then Au was released with thiourea solution, and after the sample solution cooled down graphite fur- nace atomic absorption spectrometry and inductively coupled plasma -mass spectrometry were used for determination respectively. Two methods had no significant distinction in detection limit, accuracy and precision, though compared with graphite furnace atomic absorption spectrometry, the calibration curve of inductively coupled plasma- mass spec- trometry has wide linear range, better reproducibility and faster test speed, and thus it shortens the period of geochemi- cal sample test and is worth promoting.