Hydrodealkylation of 1-Ethylnaphthalene and Its Side Reactions. A Kinetic Study

The thermal hydrodealkylation of 1-ethylnaphthalene (AEN) has been studied in a tubular flow reactor, at effective reaction temperatures in the range from 550 to 660°C. Total pressure ranged from 4 to 40 atm, and H2/ hydrocarbon molar ratio in the feed was varied from 3 to 9. Main products were naphthalene (N), 1-methylnaphthalene (AMN), acenaphthene (A), and acenaphthylene (AA). The latter is the product of a dehydrogenation which is strongly depressed at pressures of 20 atm or higher. Kinetic results in the high-pressure region have been interpreted according to a scheme of three parallel reactions of AEN (to AMN, N, and A, respectively) besides a further reaction of AMN (to N), assuming rate equations of the form r = kCarommCH2n. Arrhenius parameters and reaction orders were obtained that reproduce experimental molar conversions ± 18% on the average.