The contents and distribution patterns of rare earth elements (REEs) in coals of different geological periods from Chongqing were studied. The results show that the REE content in coals from Chongqing is 165 μg/g, much higher than that of the common Chinese coals, US coals, and the worldwide coals. The concentration of LREE is much higher than that of the heavy ones. However, the ratio of LREEs to HREEs is only 5.11, much lower than that of the ordinary coals from China. There are two types, A and B, of distribution pattern of rare earth elements in coal. The main distribution pattern is A. The distribution pattern of rare earth elements in Sinian and Cambrian stone coals and Early Permian coals is B, and it is dominated by A and followed by B of the Late Permian and Late Triassic coals. In addition, sequential chemical extraction experiments indicated that silicate association dominates the modes of occurrence of REEs in coals from Chongqing.
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