交流电弧-光电直读发射光谱同时测定碳酸盐矿物中银硼锡的方法研究  

Simultaneous Determination of Silver,Boron and Tin in Carbonate Minerals by Alternating Current-Arc Optoelectronic Direct Reading-Emission Spectrometry

作　　者：肖细炼 王亚夫 张春林 杨小丽[1,2] XIAO Xi-lian;WANG Ya-fu;ZHANG Chun-lin;YANG Xiao-li(Wuhan Center of China Geological Survey,China Geological Survey,Wuhan 430205,China;Central South China Innovation Center for Geosciences,Wuhan 430205,China)

机构地区：[1]中国地质调查局武汉地质调查中心,湖北武汉430205 [2]中南地质科技创新中心,湖北武汉430205

出　　处：《岩矿测试》2020年第5期699-708,共10页Rock and Mineral Analysis

基　　金：中国地质调查局地质调查项目(121201009000150002)。

摘　　要：银硼锡元素的丰度和变化特征可以反映区域成矿条件,指示矿床或矿化存在。碳酸盐矿物中的银硼锡是勘查地球化学及多目标地球化学中的必测元素,其测定方法是地球化学元素配套分析方案中必不可少的方法之一。由于碳酸盐矿物与普通的岩石、土壤和水系沉积物不同,该类矿物主要是灰岩、白云岩等含钙和镁元素比较高的岩石类样品,同时测定样品中银硼锡的技术难点在于高含量钙镁基体会严重干扰低含量待测元素,且摄谱过程中由于易产生二氧化碳造成样品飞溅。针对碳酸盐矿物的特殊性,本文建立了交流电弧-光电直读发射光谱同时测定碳酸盐矿物中银硼锡的分析方法。通过优化样品前处理及实验条件,用10%的盐酸处理样品,消除了基体元素钙和镁的干扰;以锗(Ge)作为内标元素进行定量,可以消除因电弧激发条件变化以及试样基体组分等外部因素造成干扰的影响;采用银与长波锗元素组成分析线对,硼和锡与短波锗元素组成分析线对,灵敏度较好;选择天然碳酸盐岩石与人工合成灰岩等12种国家一级地球化学标准物质作为标准系列,使基体组分与样品相类似;采用分析线和内标线同时扣背景的离线差减法进行背景校正。结果表明:该方法对银硼锡的检出限分别为0.008、0.49、0.18μg/g;方法精密度(RSD)对银大于10%,其余均优于10%;经国家一级地球化学标准物质验证,银硼锡测定平均值与认定值的对数差值(ΔlgC)均小于或等于±0.05,满足多目标区域地球化学调查规范的要求。BACKGROUND:The abundances and variation characteristics of silver,boron and tin reflect the regional metallogenic conditions and indicate the existence of deposits or mineralization.Silver,boron and tin in carbonate minerals are elements that must be determined in exploration geochemistry and multi-objective geochemistry.The analytical method was one of the essential methods in the matching analysis scheme of geochemical elements.Because carbonate minerals are different from common rocks,soils and water-based sediments,these minerals are mainly limestone,dolomite and other rock samples with relatively high calcium and magnesium elements,and the technical difficulty in determining silver,boron and tin in these samples is that the high content of calcium and magnesium matrix will seriously disturb the elements with low contents to be measured,and the sample is easily contaminated due to carbon dioxide during the spectrum recording process.OBJECTIVES:To solve the problems of rapid and accurate determination of silver,boron and tin in carbonate minerals.METHODS:In view of the particularity of carbonate minerals,an analytical method for the simultaneous determination of silver,boron and tin in carbonate minerals by alternating current-arc optoelectronic direct reading-optical spectrometry(AC-Arc-OES)was established.RESULTS:By using 10%hydrochloric acid to digest the sample,the interference of matrix elements,calcium and magnesium,was eliminated.Germanium was used as the internal standard element for quantitative analysis,which eliminated the influence of external factors,such as the change of arc excitation conditions and matrix composition of the sample.The silver element and the long wave germanium element were used to form the analysis line pair,and the boron and tin element and the short wave germanium element were used to form the analysis line pair with good sensitivity.Twelve national geochemical reference materials,such as natural carbonate rock and synthetic limestone,were selected as the standard series.The

关 键 词：碳酸盐矿物 银 硼 锡 盐酸处理 锗 交流电弧-光电直读发射光谱法 

分 类 号：O657.63[理学—分析化学]