小铅试金富集-电感耦合等离子体质谱法测定地球化学样品中的铂钯

摘要

建立了小铅试金富集-电感耦合等离子体质谱法测定地球化学样品中铂、钯的方法,样品处理采用小铅试金富集方法(试金扣7～11 g)代替了经典的铅试金法(试金扣40 g),碱式碳酸铅代替剧毒羰基镍,加入硝酸银保护剂,使铅扣灰吹后待测元素没有损失地进入银合粒中,干扰元素得到进一步分离,电感耦合等离子体质谱法(ICP-MS)测定铂、钯.该方法测定铂和钯的检出限分别为0.10 ng/g和 0.12 ng/g, 加入标准物质回收率为92.50 ％~106.75 ％,相对标准偏差(RSD)为2.35 ％~6.44 ％,其精密度和准确度满足要求.该方法灵敏度高、操作简便、结果准确度高,适合大批量地球化学样品的分析,在痕量贵金属的检测方面具有显著优势.%The paper establishes a method of fire assay-inductively coupled plasma mass spectrometry (ICP-MS) for the determination of platinum and palladium in geochemical samples.The method uses the fire assay (7-11 g assay button) instead of classical lead assay (40 g assay button) and basic lead carbonate instead of toxic carbonyl nickel,adds the protective agent of silver nitrate,making the elements to be detected in lead button enter silver alloy without loss after ash blowing and the interference elements further separated,and carries out the determination of platinum and palladium by inductively coupled plasma mass spectrometry.The detection limits of platinum and palladium are 0.10 ng/g and 0.12 ng/g respectively.The recoveries of standard materials are 92.50 ％-106.75 ％,and the relative standard deviations (RSD) are 2.35 ％-6.44 ％,and the accuracy and precision meet the requirements.The method has high sensitivity and is easy to operate with accurate results,which makes it suitable for the analysis of large-scale geochemical samples,especially in the detection of trace precious metals.