Group Separation And Analysis Of Organic Components Of Coals And Coal Liquefaction Derivatives

Separation and analysis of coal-based organic components is of great significance for both coal chemistry research and coal reasonable utilization. In this thesis, aimed at representative coals, organic components of five coals (Tongting, Shenfu, Getting, Pingshuo and Shengli coals, China) and liquefaction derivatives of two coals (Shenfu and Shengli coals, China) were systematically separated by ultrasonically extraction with CS₂ followed by column chromatography and analyzed GC/MS analysis.The results of coal extraction with CS₂ demonstrate the complexity of the CS₂-extractable fractions obtained from coals in their structure and composition, and further separation is needed from not only the coal chemistry research and also the production of fine chemicals.The further separation of CS₂-extractable fractions by column chromatography achieved six group fractions, including aliphatic and cycloaliphatic hydrocarbons, arenes, aromatic esters, aliphatic esters, aliphatic acids and aliphatic amides as well as two pure components, and much more organic components of coals were detected by GC/MS in the further fractions than in the original CS₂-extractable fractions. This result demonstrates the great effect of separation and analysis of coal organic components by combined use of extraction, column chromatography and modern analyzing instruments. This method can make more of coal organic components accessible than coal extraction only, affording sufficient and reliable data for coal chemistry research and coal reasonable utilization. A series of arenes with partial ring aromatized about the evolvement from abietane to retene were detected in arene fractions of Shenfu and Shengli coals, and varieties of aromatized steranes were detected in arene fraction of Shenfu coal. The detection of these components is of great significance for geochemistry research.Separation and analysis of the liquefaction oils and residues of Shengli and Shenfu coals suggest that coal liquefaction oil is essentially different with petroleum products, and great advantages exist in utilization of coal liquefaction for fine chemicals rather than for liquid fuels. Coal liquefaction oils involve large amount of arenes, certain amount of nitrogen- or oxygen-containing aromatic compounds and a tiny amount of aliphatic hydrocarbons. It can not parallel to petroleum products when used as liquid fuel, while the predominance is obvious when used for polycyclic hydrocarbons and nitrogen- or oxygen-containing aromatic compounds. Coal liquefaction residues are also precious resources for chemical industry. Based on separation and analysis of organic components of coal liquefaction oils and residues, a new assumption of coal liquefaction was proposed characterized by a primary target of value-added chemicals, further mild reaction conditions, utilization of more effective and selective catalyst and the main index of yields of oils and soluble components.This thesis innovatively studied the composition and distribution of coals and coal liquefaction derivatives by group separation and analysis, and a series of group components and a few pure compounds were obtained for the first time. This result displays a possibility of production of fine chemicals from coals and coal liquefaction derivatives through separation approach. Through this thesis a study system of separation and analysis of"CS₂ extraction-column chromatography gradient elution with hexane/ethyl acetate-GC/MS analysis"for coal-based organic components with low and middle polarity were established, making varieties of coal structural features accessible such as skeleton sections of aromatic, heterocyclic aromatic and other heteroatom structures as well as the linkages among them. This method improved the separable analysis system for coal studies and supplemented the methodology of coal chemistry research.