Process for selectively dealkylating aromatic compounds

This patent describes two processes for selectively dealkylating aromatic compounds. The first process involves reducing the concentration of organic sulfur, nitrogen, and oxygen in a coal tar stream and hydrogenating the aromatic compounds using hydrotreatment. The resulting stream is then hydrocracked to further hydrogenate the aromatic compounds and crack open rings of multiring aromatic compounds to form single-ring aromatic compounds. The single-ring aromatic compounds are then selectively dealkylated to remove alkyl groups containing two or more carbon atoms. The second process involves pyrolyzing a coal feed into a coke stream and a coal tar stream, hydrotreating the coal tar stream to reduce the concentration of sulfur, nitrogen, and oxygen, and then hydrocracking the stream to further hydrogenate the aromatic compounds and crack open rings of multiring aromatic compounds. Overall, these processes allow for the selective removal of alkyl groups from aromatic compounds, resulting in cleaner and purer products.

However, petroleum is becoming more expensive because of increased demand in recent decades.