中文摘要：

循环油是煤加氢液化反应产物中的一部分经催化加氢精制的产品，它常作为煤直接加氢液化的溶剂，既能溶解煤的液化产物和部分煤，又能供氢直接参加反应，通过催化加氢处理可以重复使用。目前，液化油作为石油替代品已得到多方面的重视，也有一些相关的报道。为了充分、合理利用循环油及提高其品质，深入研究其化学组成和结构有着重要的意义。

英文摘要：

The recycled oil from coal liquefaction was separated into three fractions （saturates, aromatics and polar fraction） by liquid chromatograph according to group composition. Each fraction was analyzed qualitatively by ^1H-NMR spectra, then the aromatic fraction was characterized using gas chromatograph/mass spectrometer （GC-MS）. It shows that liquid chromatograph is well used to separate coal liquefaction oil with high repeatability and high recovery yield. Aromatic fraction with carbon number from C10 to C21 mainly includes dicyclic-, tricyclic-and tetracyclic-hydrogenation aromatic compounds such as tetrahydronaphthalene, hydrophenanthrene, hydropyrene and their alkyl substitution compounds and so on.