To promote the development of coal-based liquid oil separation technology and maximize the utilization value of each component

the coal-based liquid oil separation methods were analyzed.Coal-based liquid oil separation can be divided into two directions:the separation of a particular component and the separation of group composition.The particular component includes phenols

heterocyclic compounds

and aromatics.The main methods to separate the particular component comprise caustic washing

solvent extraction

precipitation

complexation

liquid chromatography

liquid membrane extraction

supercritical fluid extraction

deep eutectic solvent extraction

and ionic liquid extraction.While the main methods for the separation of group composition are solvent extraction

supercritical extraction

column chromatography and high performance liquid chromatography.Each method has its advantages and disadvantages.These methods are roughly divided into four categories based on the separation mechanism between separation agent and target product:the third substance produced by chemical reaction

changing the solubility

taking advantage of the difference of adsorption capacity

forming the hydrogen bond and conjugation effect.At last

the improved proposals and prospects are suggested.