Trace element quantification in solid fuel wastes by LA-ICP-MS: a review

Laser Ablation Inductively Coupled Plasma Mass Spectrometry (LA-ICP-MS) has emerged as a pivotal analytical technique for trace element determination in solid fuel wastes (e.g., coal fly ash, biomass-derived char, petroleum coke residues), owing to its high sensitivity (ng/g-level limits of detection), micron-scale spatial resolution (1-100 μm), and capability for simultaneous multi-element analysis. This technique enables in situ micro-area characterization without complex sample preparation, precisely mapping the spatial distribution of hazardous metals (Pb, Cd, Cr) and Rare Earth Elements (REEs) within heterogeneous matrices (e.g., silicate glass phases vs. porous carbon interfaces). Such insights are crucial for assessing environmental risks (e.g., ecotoxicity) and evaluating the potential for resource recovery (e.g., REE-enriched micro-domains with concentrations exceeding 500 μg/g in coal ash). However, challenges persist due to the compositional complexity of solid fuel wastes, including matrix-dependent fractionation, scarcity of calibration standards, and limitations in universal calibration strategies. Future research must prioritize: i) Optimizing sample preparation protocols; ii) Advancing calibration strategies; and iii) Integrating complementary analytical techniques. By harmonizing technological innovations with standardization, LA-ICP-MS shows promise in advancing precise environmental risk assessment and high-value resource recovery from solid fuel wastes, thereby contributing to sustainable waste management in line with carbon neutrality goals.