Abstract:The efficient and accurate determination of trace elements in coal-series samples, such as coal, coal ash, and coal fly ash, is crucial not only for assessing their environmental behavior and controlling pollution but also for the comprehensive utilization of these resources. This study established an optimal pre-digestion protocol by systematically investigating digestion systems and temperature control programs. To mitigate mass spectrometric interferences, including polyatomic and isobaric interferences, effective strategies such as the introduction of internal standard elements, application of interference correction equations, and utilization of Kinetic Energy Discrimination (KED) mode were implemented. The analytical method was rigorously validated using certified reference materials, resulting in the development of a robust quantitative procedure for determining 11 trace elements (Be, V, Cr, Co, Cu, Zn, As, Cd, Pb, Th, U) based on microwave digestion coupled with inductively coupled plasma mass spectrometry (ICP-MS).The results demonstrated that complete digestion of the samples was achieved using a mixed acid system of HNO?-HF in a microwave digester, employing a three-step temperature ramp with a final temperature of 200°C held for 40 minutes. The digest was then subjected to acid removal prior to ICP-MS analysis. Under the optimized conditions with a sample mass of 0.05 g and a final dilution volume of 50 mL, the method detection limits ranged from 0.01 to 0.5 mg/kg. The accuracy and precision of the method were confirmed through the analysis of CRMs and spiked recovery experiments. The relative errors (RE) for all target elements fell within the range of -7.20% to 6.27%, while the spike recovery rates varied from 91.2% to 102%. The relative standard deviations (RSD) were between 1.52% and 5.01%, indicating excellent reproducibility.The practical applicability of this method was further verified by the successful analysis of three types of real-world samples: coal, coal ash, and coal fly ash. The method proved suitable for the simultaneous determination of multiple trace elements across diverse coal-series matrices. This developed methodology overcomes the limitations associated with conventional techniques, which are often restricted to a single sample type and suffer from drawbacks such as incomplete decomposition, potential contamination, and cumbersome operational procedures. Consequently, it provides an efficient, simplified, environmentally friendly, and highly adaptable multi-element analytical approach for complex coal-series samples.