Processes are provided for producing triphenylene by combining at least dodecahydrotriphenylene, a dehydrogenation catalyst such as palladium on carbon, and an aliphatic solvent having a boiling point greater than 180° C. to form a reaction mixture, heating the reaction mixture to at least about 180° C. but lower than the boiling point of the aliphatic solvent, maintaining the temperature of the reaction mixture at 180° C. but lower than the boiling point of the aliphatic solvent, and passing a purge fluid comprising an inert fluid through the reaction mixture, for a period of time adequate for production of triphenylene.