碱熔、分离沉淀—电感耦合等离子体质谱法快速测定地球化学样品中的锡

Alkalinefusion,separate precipitation-inductively coupled plasma mass spectrometry and rapid measurement of tin from planet chemical samples

利用样品处理过程中,试液加入内标混匀后不需精确定容的特点,通过过滤分离沉淀、减少基体影响,采用硝酸酸化、避免氯离子干扰进行方法改进。样品经氢氧化钠熔融,热水提取,过滤分离沉淀,硝酸酸化后加入铑内标,粗略定容,电感耦合等离子体质谱仪测定,建立了一套快速、准确、批量测定地球化学样品中锡的方法。该方法经国家一级标准物质验证,分析结果与标准值吻合,相对标准偏差(RSD,n=6)落在4.8%~9.6%之间,方法检出限为锡:0.27μg/g。该方法操作简单、快速、易于掌握,线性范围宽,准确度和精密度均能满足地质找矿需要,已成功应用于本中心大批量地球化学样品锡元素的测定。

Based on the characteristic that constant volume need not to be precisely measured when test solution being mixed with internal standardized materials during the processing of samples, the measurement can be improved by reducing matrix influence through filtering, separation and precipitation, as well as avoiding chloride ion through acidizing of nitric acid. When samples were melted by sodium hydroxide, extracted by hot water, filtered and separated by precipitation, acidized by nitric acid, and added with internal standardized rhodium, the constant volume can be roughly measured and determined by the inductively coupled plasma mass spectrometer, therefore a rapid and accurate method to measure tin from massive planet chemical samples can be established. The analysis result of this method matches with standard value, which has been verified by national first-class standard materials, and the RSD （n = 6） ranges between 4. 8% and 9. 6%, according to which, this material can be defined as tin with 0. 27 μg/g. The advantages of this method are simple, rapid, easy to handle, broad linear range, highly precise and accurate, which could meet the need of geographic minerals searching. This method has been successfully applied in the measurement of tin from massive planet chemical samples.