摘要: 目前煤灰中钙、镁测定采用的是EDTA络合滴定分析方法，制样比较复杂，整个测定过程耗时长、操作要求较严格。采用高氯酸和氢氟酸对样品进行消解处理，再用盐酸溶出，以高纯水为溶剂，选用Ca396.847nm、Mg279.553nm为分析谱线，采用电感耦合等离子体原子发射（ICP-OES）法测定煤灰中钙、镁含量，钙、镁元素校准曲线相关系数均大于0.999 9，检出限分别为0.000 2%，0.000 1% ，定量检出线分别是0.000 6%、0.000 5%，测定5个煤灰样品结果的相对标准偏差（RSD，n=5）为1.86%～3.04%，加标回收率为97%～102%。该测定方法操作简单、分析效率高、精密度和准确度高，对生产的指导作用强，可以用于煤灰中钙、镁的测定。
关键词: 电感耦合等离子体原子发射（ICP-OES）光谱法；煤灰组分；钙；镁

Abstract: EDTA complex titration analytical method is currently adopted to determine the calcium and magnesium content in coal ash. However, it is complicated in sample making, time-consuming in the whole process and strict in operation requirements. In this study, samples are firstly discomposed by perchloric acid and hydrofluoric acid and then dissolved by hydrochloric acid. Using high-purity water as the solvent, Ca396.847 nm and Mg279.553 nm as analytical spectral lines, the study determines the calcium and magnesium contents in coal ash by the method of Inductively Coupled Plasma-Optical Emission (ICP-OES). The correlation coefficients of the calibration curves for calcium and magnesium are both greater than 0.9999. The limit of detection (LOD) are 0.000 2% and 0.000 1% and the limit of quantification (LOQ) are 0.000 6% and 0.000 5%, respectively. The relative standard deviations (RSDs, n=5) of the five samples are in the range of 1.86%-3.04%, and the recovery were in the range of 97%-102%. The method is simple in operation, high in analytical efficiency, precision and accuracy, has a strong guiding effect on production, and can be used to determine calcium and magnesium in coal ash.
Keywords: Inductively coupled plasma atomic emission (ICP-OES) spectrometry; coal ash composition; Calcium; Magnesium