Coal hydroaromatic systems

Isomerization and Adduction of Hydroaromatic Systems at Conditions of Coal Liquefaction... 

Promotion of Hydrogen Exchange The radicals derived from the coal molecules by simple thermal homolyses and by molecule-induced homolyses initiate exchange reactions between tetralin-d, and the donors in the reaction system—principally diphenyl-methane and the hydroaromatic compounds in the macerals (2. ... 

Beiersetal. (1985). In these systems, most of the acetylene was not produced from primary methane released from coal, but came from hydroaromatic compounds as well as aromatic hydrocarbons including benzene, toluene, ethyl benzene, and anthracite oil. 

There is indirect evidence for the presence of nitrogen ring systems in coal— the following compounds have been identified by mass spectroscopy as being present in coal tar pitch pyridines, pyrroles, quinolines, azapyrenes, benzacridines, dibenzacridines, and substituted carbazoles. Allowances must be made for any structural alterations during the thermal production of the pitch as well as for aromatization of any hydroaromatic ring systems. 

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