Abstract

Sample preparation is the most crucial step in any analytical method of determination. The main goal of sample preparation is to isolate or pre-concentrate target analyte from complex matrix, to ensure compatibility of the desired analyte with the detection technique of interest. Most plasma-based spectrometric techniques cannot succeed with high matrix interferences. The favored sample preparation method must follow the Green Analytical Chemistry Principles (i.e., short duration, environmentally friendly reagents, less energy consumption, microliter volume, robust, simple, cost-effective, etc.). Rare earth elements (REEs) naturally occur in complex matrices (fossil fuels and geological materials) at trace concentration levels. Therefore, this review evaluates various sample preparation methods that have been frequently reported for the determination of REEs in geological and fossil fuel samples using plasma-based analytical techniques such as inductively coupled plasma optical emission spectroscopy and inductively coupled plasma mass spectrometry. Moreover, the determination of these REEs is examined according to whether the samples were acid digested, heat digested, or extracted prior to REEs spectrometric determination. Lastly, the merits and demerits of each sample preparation method are extensively discussed and the recent trends on the development of plasma-based techniques for REEs determination in geological and fossil fuel samples are addressed.

摘要

样品制备是任何分析测定方法中最关键的步骤。样品制备的主要目的是从复杂基质中分离或预浓缩目标分析物，以确保所需分析物与目标检测技术兼容。大多数基于等离子体的光谱技术无法在高基质干扰下获得成功。首选的样品制备方法必须遵循绿色分析化学原理（即持续时间短，环保试剂，能耗少，微升体积小，坚固，简单，具有成本效益等）。稀土元素（REE）自然存在于复杂的基质（化石燃料和地质材料）中，浓度为痕量。因此，这篇综述评估了使用基于等离子体的分析技术（例如电感耦合等离子体发射光谱和电感耦合等离子体质谱法）测定地质和化石燃料样品中稀土元素的多种样品制备方法。此外，根据稀土元素光谱测定之前样品是否经过酸消解，热消解或提取来检查这些稀土元素的确定。最后，对每种样品制备方法的优缺点进行了广泛讨论，并探讨了基于等离子体的地质和化石燃料样品中REEs测定技术发展的最新趋势。