Platinum group metals (PGMs) present a variety of forms in the environment, and analysis of speciation is essential for identifying their ecological risk. Here, we reviewed the methods for the morphological analysis of three major PGMs (platinum, palladium and rhodium) in the environment, including chemical sequential extraction, hyphenated techniques for instruments, computer simulations. We outlined the types, characteristics and applications of these methods, elaborated the weaknesses, and provided prospects for future development. Among them, chemical sequential extraction is universally applied in the morphological analysis of solid-phase samples, with diverse extraction conditions and procedures proposed in the current study. However, it has not been well standardized. The hyphenated techniques for instruments have significant advantages for the determination of elemental forms in solution, of which capillary electrophoresis system can separate similar substances with the same electrophoresis ability. Liquid chromatography systems have better performance in terms of separation capacity and detection limit. The computer simulations further expand the access to morphological analysis, enabling complex morphological calculations. It was proposed to combine multiple methods in the future to continuously improve the accuracy of analytical techniques by complementing and optimizing each other.
环境中铂族金属(PGMs)的赋存形态多样,形态分析对识别其生态风险具有十分重要的意义。本文综述了环境中3种主要铂族金属(铂、钯、铑)的形态分析方法,包括化学顺序提取、仪器联用技术及计算机模拟等,概述了这些方法的类型、特点及应用,同时阐述了它们存在的不足,并对未来发展方向进行了展望。化学顺序提取法普遍用于固相样品形态分析,当前研究中提出的提取条件和步骤多样,但不能很好地标准化;仪器联用技术在溶液元素形态分析上具有显著优势,毛细管电泳联用系统能够分离具有相同电泳能力的相似物质,但在分离能力和检出限方面不如液相色谱联用系统;计算机模拟则进一步拓展了形态分析的途径,能够实现复杂的形态计算。建议今后将多个方法进行结合,通过相互补充与完善,不断提高分析技术准确性。.
Keywords: chemical sequential extraction; computer modelling; hyphenated technique; morphological analysis; platinum group metals (PGMs).