目前,煤中铀的测定大都采用碳酸钠小体积沉淀分离、铀试剂Ⅲ显色分光光度法,但该法对低含量(<5PPM)的测定结果偏高。本文通过试验,拟定了煤样经低温灰化,氢氟酸—硝酸—硫酸—高氯酸分解,TBP萃淋树脂分离,偶氮胂Ⅲ显色来测定煤中轴的方法。实验证明该法的灵敏度和选择性均较好,适用于煤中含铀量在PPM级以上的测定。 At present, most of the determination of uranium in coal using sodium carbonate small volume precipitation separation, uranium reagent Ⅲ color spectrophotometry, but the method of low content (<5PPM) determination of high. In this paper, the method of determining the coal axis by means of low temperature ashing, hydrofluoric acid - nitric acid - sulfuric acid - perchloric acid decomposition, TBP extraction resin separation and arsenazo Ⅲ chromogenic assay was developed. Experiments show that the sensitivity and selectivity of the method are good, suitable for determination of uranium content in coal above the PPM level.