原油、沥青中的各种微量元素信息已被应用于油气勘探和油气地球化学研究,然而相关的分析方法较少,而且前处理过程繁琐。本文将微波消解法应用于沥青样品的消解,建立了微波消解-电感耦合等离子体质谱法测定16种稀土元素的方法。不同组合消解试剂优化实验研究表明,HNO3-HF作为消解试剂效果最好,并讨论了样品量、消解条件、质谱干扰等影响因素。该方法样品处理简单,并应用于实际样品的分析,方法的精密度(RSD,n=8)小于6.2%,稀土元素检出限在0.0001~0.013μg/g之间,标准样品分析结果均在推荐值误差范围之内,为沥青类样品中稀土元素分析测定提供了新的参考方法。
A method for the determination of 16 rare earth elements in solid bitumen was established by inductively coupled plasma-mass spectrometry with microwave digestion.The bitumen sample was digested in closed vessels by microwave using HNO3-HF at elevated temperature and pressure.The experimental conditions,the factors affecting determination and mass interferences were discussed.The proposed method was applied to the determination of 16 rare earth elements in solid bitumen.The analysis results of standard reference material NIST 1632d(coal)showed that the method could be used to digest the bitumen sample quickly.The relative standard deviation of the method was less than 6.2%(n=8),and the detection limit was between 0.0001 and 0.013μg/g.It can provide a new reference method for the determination of rare earth elements in solid bitumen.