微敞开石墨消解-电感耦合等离子体质谱(ICP-MS)法测定橡胶制品中稀土元素含量

Determination of Rare Earth Elements Content in Rubber Products by Inductively Coupled Plasma Mass Spectrometry (ICP-MS) with Micro-open Graphite Digestion

稀土元素会对橡胶的性能造成影响,需加强监控。通过系统分析消解试剂、消解温度以及消解时间等因素对检测分析的影响,对设备工作功率、步距深度、冷却气流速、辅助气流速、雾化气流速等质谱参数进行优化筛选,利用在线内标手段校正基体效应和信号漂移等问题,利用微敞开石墨消解技术结合电感耦合等离子体质谱仪,构建了测定天然橡胶制品中16种稀土元素含量的方法。微敞开石墨消解橡胶制品的较优处理条件以6 mL HNO_(3)、1 mL HClO_(4)和4 mL HF为消解试剂,采用三阶程序升温,消解最高温度至180℃,保温180 min。结果表明,稀土元素的检出限为0.0002~0.001 mg/kg,方法加标回收率在71.1%~90.9%,相对标准偏差RSD在3.8%~9.2%,各元素的标准曲线线性关系良好。与传统方法相比,微敞开石墨消解技术操作简便,可按照设定程序自动完成消解全过程,无需单独赶酸,工作效率较高,且具有成本低、检测范围宽、检出限低、处理效率高等优点,适用于橡胶制品中稀土元素的高通量检测。

Rare earth elements can have an impact on the performance of rubber,and monitoring needs to be strengthened.The influences of factors such as digestion reagent,digestion temperature and digestion time on the detection and analysis were systematically analyzed.The mass spectrometry parameters,such as the working power of the equipment,sampling depth,cooling gas flow rate,auxiliary gas flow rate,and atomization gas flow rate,were optimized and screened,and the matrix effect and signal drift that occurred during the detection process were also corrected by using online internal standard means.A method for determining the content of 16 rare earth elements in natural rubber products was developed using micro open graphite digestion technology combined with inductively coupled plasma mass spectrometry.It was shown that the micro-open graphite ablation of rubber products had the following optimal processing conditions:6 mL HNO_3,1.5 mL HClO_(4) and 4 mL HF as the ablation reagents,and the third-order program was used to elevate the temperature,with the maximum temperature of the ablation up to 180 ℃,and the heat preservation was carried out for 180 min.The results showed that the detection limit of rare earth elements was ranged from 0.000 2—0.001 mg/kg,the method recovery was between 71.1% and 90.9%,the relative standard deviation(RSD) was between 3.8% and 9.2%.The linear relationship between the standard curves of each element was good.Compared with the traditional method,the micro-open graphite digestion technique is easy to operate,and it can automatically complete the whole process of digestion according to the set program,without the need to drive the acid separately,so the working efficiency is higher.This method has the advantages of low cost,wide detection range,low detection limit,and high processing efficiency,and it is suitable for the high-throughput detection of rare earth elements in rubber products.