HYDRODEALKYLATION REACTION OF ETHYLBENZENE OVER A SUPPORTED NICKEL-TUNGSTEN CATALYST

The hydrodealkylation reaction of ethylbenzene over a supported nickel-tungsten catalyst has been studied. Over a supported nickel catalyst, the dominant ring opening reaction of benzene over 400-degrees-C led to high methane selectivity. On the other hand, over a cosupported nickel-tungsten catalyst, the ring opening reaction was suppressed, thus resulting in high benzene selectivity. The activity and selectivities of the hydrodealkylation reaction were dependent on the degree of reduction of tungsten. Using an oxygen titration method, the presence of nickel in the cosupported catalysts was confirmed to promote the reduction of tungsten. The cosupported nickel-tungsten catalysts suppressed the decomposition of dioxane in temperature-programmed desorption experiments more than the supported nickel catalyst.