电感耦合等离子体质谱法测定甘肃文县阳山金矿床原生晕样品中金  

Determination of gold in primary halo sample from Yangshan gold deposit in Wenxian County of Gansu Province by inductively coupled plasma mass spectrometry

作　　者：陆海川 叶芝祥[2] 丁洋 熊韬 龚仓 LU Haichuan;YE Zhixiang;DING Yang;XIONG Tao;GONG Cang(Civil-Military Integrated Geological Survey Center of China Geological Survey,Chengdu 610036,China;College of Resources and Environment,Chengdu University of Information Engineering,Chengdu 610225,China)

机构地区：[1]中国地质调查局军民融合地质调查中心,四川成都610036 [2]成都信息工程大学资源环境学院,四川成都610225

出　　处：《冶金分析》2022年第1期64-70,共7页Metallurgical Analysis

基　　金：2019年甘肃阳山金矿岩金普查项目(DD20191028)。

摘　　要：甘肃文县阳山金矿床原生晕样品中的金含量在μg/g到ng/g之间变动,高值异常点多(0.5~15.4μg/g),测试过程金记忆效应问题突出。选择采用70 mL王水(1+1)对甘肃文县阳山金矿床原生晕样品进行消解,用聚氨酯泡沫塑料对金进行吸附富集,以3 g/L硫脲溶液进行脱附,以铼(5 ng/mL)为内标选择在线内标法进行校正,实现了电感耦合等离子体质谱法(ICP-MS)对甘肃文县阳山金矿床原生晕样品中金的测定。采用实验方法对金含量较高的原生晕样品Y2-1(w(Au)=5.14μg/g)测定后,选用2%硝酸和3 g/L硫脲溶液为清洗溶液对管路进行清洗,再对空白进行测定。结果表明,选用3 g/L硫脲溶液作为清洗溶液,效果优于2%硝酸;当用3 g/L硫脲溶液清洗30~90 s时,空白值接近于0,故实验选用3 g/L硫脲溶液冲洗30 s来消除金记忆效应的影响。校准曲线的相关系数为0.999 8,线性范围为0.12~500 ng/g,方法检出限为0.03 ng/g,定量限为0.12 ng/g。按照实验方法,对7个化探金及矿石金分析标准物质中金进行测定,结果与认定值相吻合;选择3个不同种类的原生晕样品Y3-1(千枚岩)、Y3-2(破碎蚀变千枚岩)、Y3-3(斜长花岗斑岩金矿体),按照实验方法各进行6次平行测定,并分别加入一定量的金标准溶液进行加标回收试验,测定结果的相对标准偏差(RSD,n=6)在5.3%~9.0%之间;回收率在90%~105%之间。选取3个不同类型的原生晕样品,按照实验方法进行测定,并采用石墨炉原子吸收光谱法(GFAAS)进行方法比对,两种方法测定结果基本一致。The gold content in primary halo sample from Yangshan gold deposit in Wenxian County of Gansu Province varied from μg/g to ng/g. There are many high value outliers(0.5-15.4 μg/g), and the memory effect of gold in determination is outstanding problem. The primary halo sample from Yangshan gold deposit in Wenxian County of Gansu Province was digested with 70 mL of aqua regia(1+1). The gold was adsorbed and enriched with polyurethane foaming plastic followed by desorption with 3 g/L thiourea solution. The on-line internal standard method using rhenium(5 ng/mL) as internal standard was selected for correction. The determination of gold in primary halo sample from Yangshan gold deposit in Wenxian County of Gansu Province by inductively coupled plasma mass spectrometry(ICP-MS) was realized. The primary halo sample with relatively high gold content [Y2-1(w(Au)=5.14 μg/g)] was determined according to the experimental method. Then the pipelines were cleaned with 2% nitric acid and 3 g/L thiourea solution before determination of blank. The results showed that the cleaning effect of 3 g/L thiourea solution was better than 2% nitric acid. When the cleaning time with 3 g/L thiourea solution was in range of 30-90 s, the value of blank was close to 0. Therefore, the pipelines were cleaned with 3 g/L thiourea solution for 30 s to eliminate the influence of memory effect of gold. The correlation coefficient of calibration curve was 0.999 8. The linear range was 0.12-500 ng/g. The limit of detection was 0.03 ng/g, and the limit of quantification was 0.12 ng/g. The contents of gold in seven certified reference materials of geochemical prospecting and gold for the analysis of gold were determined according to the experimental method. The results were consistent with the certified values. Three primary halo samples with different types(Y3-1 phyllite, Y3-2 tattered altered phyllite, and Y3-3 plagioclase granite porphyry gold ore) were selected and determined for 6 times according to the experimental method. Moreover, certain amount

关 键 词：电感耦合等离子体质谱法(ICP-MS) 原生晕样品 记忆效应 金 

分 类 号：O657.63[理学—分析化学]