高海拔地区原子吸收法测定地质样品中金的最佳条件探讨

针对高海拔地区大气压低，水沸点低，金的溶出率低，富集金的泡沫塑料在硫脲溶液中的解脱率低等问题，比较了高原地区与平原地区在相同条件下的测定结果，探讨了溶矿时王水浓度对金溶出率的影响；比较了2种溶矿方法、泡沫塑料吸附的温度和泡沫塑料的解脱方法等对测定结果的影响。通过多次试验，确定了高海拔地区测定金的最佳条件。该方法经国家一级标准物质分析验证，结果与标准值相符。方法的精密度（RSD，n=6）为2.85%～4.37%，检出限为0.03 μg/mL，适用于高海拔地区地质样品中金的分析，较好地解决了高原地区低压环境下样品中金测定的技术难题。

Discussion on the Optimum Conditions for Determination of Gold in Geological Samples by Atomic Absorption Spectrometry at High Altitude Area

Aiming at the problems of low atmospheric pressure，low boiling point，low dissolution rate of gold，low release rate of the plastic foam containing gold in thiourea solution at high altitude area，the determination results of plateau and plain areas were compared under the same conditions，and the effect of aqua regia concentration on the dissolution rate of gold was discussed.At the same time，the main influence factors of the determination results were compared，such as two ore dissolving methods，foam adsorption temperature，release method of foam plastics.The optimum conditions for determining gold at high altitude area were obtained through many experiments.The method has been varified by determination of national standard reference material，and the results are consistent with the standard values.The precision of the method is 2.85% to 4.37% with RSD（n=6），and the detection limit is 0.03 μg/mL.The method is suitable for gold analysis in geological samples at high altitude，it solves the technical problem of the determination of gold under low pressure environment in plateau area.