泡沫富集—火焰原子吸收光谱法测定多金属矿石中的Au

Determination of Gold in Polymetallic Ore by Polyurethane Foam Concentration and Flame Atomic Absorption Spectrometry

矿样先破碎、缩分再经棒磨机打磨成样品,后在马弗炉中焙烧除硫及有机质等杂质,在通风橱中的电热板上用1＋1王水60 m L溶解30分钟。溶解后的金在15%王水介质中被动态的泡塑吸附富集,泡塑洗净后移入比色管中加入1%硫脲溶液在沸水浴中解脱（Au）30分钟,趁热取出泡塑,溶液直接用火焰原子吸收光谱法—标准曲线法快速测定。矿样在0.00~25.00 ug/m L范围内呈良好的线性关系（二次拟合后相关系数r为1.0000）,实验采用空白实验、平行样实验、国家标准物质重复实验进行实验质量控制。分析结果具有很好的精密度和准确度,符合地质测试质量规范要求。本文就该方法大批量测定Au在实际生产中的应用进行简要探讨。

After being crushed to pieces, reduced and polished to be samples with a rod mill, ore is roasted with aqua regia（1∶1, 60 m L） on an electric hot plate which is in a fume cupboard for 30 minutes to get rid of sulphur and organic matter. Dissolved gold at 15 % aqua regia medium is absorbed by polyurethane foam. After being cleaned, polyurethane foam is moved into a colorimetric tube and then disentangled in boiling water with 1 % thiourea for 30 minutes. Take out polyurethane foam when it is hot. The solution is directly determined by flame atomic absorption spectrometry. The ore has a good linear relationship within the scope of 0.00 to 25.00 ug/m L（after quadratic fitting, the correlation coefficient r is 1.0000）. The experiment adopts different kinds of ways to control the quality of experiment, such as blank experiment, parallel sample experiment, certified reference materials. The analysis results have good precision and accuracy; conform to the requirements of the geological testing quality specifications. The paper briefly discusses its application in practical production of the method of mass determination of Au.