Wang Shunxiang, Gong Cang, Wang Hongcheng, Xia Xiang, Liu Jiufen, Lu Haichuan
Research Center of Applied Geology of China Geological Survey Chengdu 610036 China
Natural Resources Comprehensive Survey Command Center of China Geological Survey Beijing 100055 China.
RSC Adv. 2025 Jun 18;15(26):20724-20733. doi: 10.1039/d5ra02280k. eCollection 2025 Jun 16.
At present, due to the uneven distribution and low content of gold (Au) in rock gold ore samples, the separation, enrichment and accurate determination of Au have become daunting tasks in the analysis of rock gold samples. This study established a method for determining the Au content in rock gold ore samples with the advantages of high efficiency, low cost, safety and more environment-friendliness. It was based on closed water bath digestion-polyurethane foam (PUF) enrichment and thiourea release, and then, flame atomic absorption spectrometry was used to determine the Au content. By eliminating interference and optimizing the PUF pretreatment method, aqua regia dosage, water bath dissolution time, oscillation frequency and time, thiourea concentration, release time and temperature and other working conditions, technical problems such as the low adsorption efficiency of the PUF and interference from tungsten, antimony and iron elements were solved. The Au detection limit of this method was 0.03 μg g, the lower limit of determination was 0.1 μg g, and the optimal determination range was 0.1-40 μg g. This method was used to determine 7 national standard materials of gold ores with different high and low contents (GBW07808b, GBW07809b, GBW07297a, GBW07298, GBW07300a, GBW(E)070012a and GBW07807a); the relative error (RE) was ≤3.06% and the relative standard deviation (RSD) was ≤8.35%. This method was performed in 9 laboratories to compare and verify the 7 national standard materials of gold ores with different high and low contents (GBW(E)070067, GBW(E)070262, GBW(E)070138a, GBW07300a, GBW07809b, GBW(E)070141 and GBW07298a); the RE was ≤10.55% and the RSD was ≤3.93%, achieving good results. A total of 85 rock gold ore samples were selected for determination using this method and compared with the results of activated carbon enrichment-flame atomic absorption spectrometry. The qualification rate was 97.65%, and the analysis and testing efficiencies were improved by nearly 10 times.
目前，由于岩金矿样品中金（Au）分布不均且含量较低，金的分离、富集及准确测定已成为岩金样品分析中的艰巨任务。本研究建立了一种测定岩金矿样品中金含量的方法，该方法具有高效、低成本、安全且更环保的优点。它基于封闭水浴消解 - 聚氨酯泡沫（PUF）富集及硫脲解脱，然后采用火焰原子吸收光谱法测定金含量。通过消除干扰并优化PUF预处理方法、王水用量、水浴溶解时间、振荡频率和时间、硫脲浓度、解脱时间和温度等工作条件，解决了PUF吸附效率低以及钨、锑和铁元素干扰等技术问题。该方法的金检测限为0.03 μgg，测定下限为0.1 μgg，最佳测定范围为0.1 - 40 μgg。用该方法测定了7种不同高低含量的金矿石国家标准物质（GBW07808b、GBW07809b、GBW07297a、GBW07298、GBW07300a、GBW(E)070012a和GBW07807a）；相对误差（RE）≤3.06%，相对标准偏差（RSD）≤8.35%。该方法在9个实验室进行，对7种不同高低含量的金矿石国家标准物质（GBW(E)070067、GBW(E)070262、GBW(E)070138a、GBW07300a、GBW07809b、GBW(E)070141和GBW07298a）进行了比对验证；RE≤10.55%，RSD≤3.93%，取得了良好结果。采用该方法共测定了85个岩金矿样品，并与活性炭富集 - 火焰原子吸收光谱法的结果进行比较。合格率为97.65%，分析测试效率提高了近10倍。
