次氯酸氧化ICP-MS同时测定金矿石中金和伴生元素银铜铅锌砷锑  

Simultaneous Determination of Au and Associated Elements Ag,Cu,Pb,Zn,As and Sb in Gold Ore by ICP-MS with Hypochloric Acid Oxidation

作　　者：王啸 刘玖芬 甘黎明 李荣华 王西 魏欣 何涛 WANG Xiao;LIU Jiufen;GAN Liming;LI Ronghua;WANG Xi;WEI Xin;HE Tao(Xi’an Center of Mineral Resources Survey,China Geological Survey,Xi’an 710100,China;China University of Geosciences(Beijing),Beijing 100083,China;Command Center for Natural Resources Comprehensive Survey,China Geological Survey,Beijing 100055,China)

机构地区：[1]中国地质调查局西安矿产资源调查中心,陕西西安710100 [2]中国地质大学(北京),北京100083 [3]中国地质调查局自然资源综合调查指挥中心,北京100055

出　　处：《岩矿测试》2025年第2期268-278,共11页Rock and Mineral Analysis

基　　金：中国地质调查局地质调查项目(DD20242769);中国地质调查局自然资源综合调查指挥中心科技创新基金项目(KC20230012);中国地质调查局地质调查项目“全国金矿重点调查区调查评价项目”(DD20230060)。

摘　　要：金矿石是重要的战略性矿产资源,除需检测金含量外,还需检测银铜铅锌砷锑等伴生元素含量。由于金矿石中往往含有碳质物和硫化物,对金的浸出有影响,现有方法需要焙烧-消解-预富集后测定,矿物中硫化砷、氧化砷、卤化锑等化合物沸点均低于565℃,金矿石在650℃焙烧时砷、锑极易损失,因此银铜铅锌砷锑需单独消解测定,极为繁琐。本文利用次氯酸的强氧化性,在硝酸介质中氧化碳质物与硫化物替代焙烧样品,结合离线内标建立了电感耦合等离子体质谱(ICP-MS)同时测定金银铜铅锌砷锑的方法。研究了次氯酸用量、消解时间、内标和干扰元素对分析结果的影响,结果表明10.0000g样品加入20mL硝酸和5mL次氯酸于电热板沸腾溶解近干,可将碳质物与硫化物完全氧化,稀释因子为1000时金银铜铅锌砷锑的检出限分别为0.03、0.05、0.19、0.26、0.22、0.27、0.05μg/g。应用本方法对高品位碲金矿成分分析标准物质(GBW07858、GBW07859)进行测定,结果与标准值相符;对5个不同类型的金矿石实际样品进行测定,结果与《金矿石化学分析方法》(GB/T 20899—2019)单独测定结果相符,各元素相对误差均≤5.32%,相对标准偏差(RSD,n=7)≤4.71%。本方法解决了金与银铜铅锌砷锑等伴生元素无法同时测定的问题,并省去了焙烧样品与金预富集步骤,流程简便。Gold ore contains a certain amount of gold,silver,copper,lead,zinc,arsenic,and antimony.Gold needs to be determined after roasting,digestion and enrichment;arsenic and antimony are lost after roasting,while silver,copper,lead,zinc,arsenic and antimony need to be separately determined,which is extremely cumbersome.The experiment utilized the oxidizing properties of hypochlorous acid to oxidize carbonaceous materials and sulfides in a nitric acid medium instead of sample roasting.Combined with offline internal standards,a method was established for the simultaneous determination of gold,silver,copper,lead,zinc,arsenic,and antimony by ICP-MS.The amount of hypochlorous acid,digestion time,internal standard selection,and interfering elements were optimized.The results showed that the carbonaceous and sulfides materials were oxidized under the conditions of 10.0000g of the sample,20mL of nitric acid and 5mL of hypochlorous acid with using a heating plate to deal with them until near-dryness.According to the experimental method,gold,silver,copper,lead,zinc,arsenic,and antimony were determined in five different types of gold ore samples,the results were consistent with the national standard method,and the relative standard deviations(RSDs,n=7)were less than 4.71%.This method solves the problem of simultaneous determination of gold,silver,copper,lead,zinc,arsenic and antimony,which is simple and convenient.

关 键 词：次氯酸 电感耦合等离子体质谱法 金矿石 金 伴生元素 

分 类 号：O657.31[理学—分析化学]