Departamento de Química, Universidade Federal de Santa Maria, 97105-900 Santa Maria, RS, Brazil.
Anal Chim Acta. 2012 Oct 9;746:15-36. doi: 10.1016/j.aca.2012.08.009. Epub 2012 Aug 14.
In this review sample preparation strategies used for crude oil digestion in last ten years are discussed focusing on further metals and non-metals determination. One of the main challenges of proposed methods has been to overcome the difficulty to bring crude oil samples into solution, which should be compatible with analytical techniques used for element determination. On this aspect, this review summarizes the sample preparation methods for metals and non metals determination in crude oil including those based on wet digestion, combustion, emulsification, extraction, sample dilution with organic solvents, among others. Conventional methods related to wet digestion with concentrated acids or combustion are also covered, with special emphasis to closed systems. Trends in sample digestion, such as microwave-assisted digestion using diluted acids combined with high-efficiency decomposition systems are discussed. On the other hand, strategies based on sample dilution in organic solvents and procedures recommended for speciation analysis are reported as well as the use of direct analysis in view of the recent importance for crude oil field. A compilation concerning sample preparation for crude oil provided by official methods as well as certified reference materials available for accuracy evaluation is also presented and discussed.
本文综述了过去十年中用于原油消解的样品前处理策略，重点讨论了进一步测定金属和非金属元素的方法。所提出方法的主要挑战之一是克服将原油样品完全消解为溶液的困难，该溶液应与用于元素测定的分析技术相兼容。在这一方面，本文综述了原油中金属和非金属元素测定的样品前处理方法，包括湿法消解、燃烧、乳化、萃取、用有机溶剂稀释样品等。同时还涵盖了与浓酸湿法消解或燃烧有关的常规方法，特别强调了封闭系统。讨论了样品消解的发展趋势，例如使用稀酸和高效分解系统的微波辅助消解。另一方面，本文还报道了基于有机溶剂稀释样品和用于形态分析的建议程序的策略，以及鉴于最近对原油领域的重要性，直接分析的应用。本文还提供了有关官方方法提供的原油样品前处理以及可用于准确性评估的认证参考物质的汇编，并进行了讨论。
