Nonmetallic boron nitride embedded graphitic carbon catalyst for oxidative dehydrogenation of ethylbenzene

Abstract

Oxidative dehydrogenation of ethylbenzene to styrene featured with a non-equilibrium-limit is an alternative to the direct dehydrogenation process, but often exhibits low styrene selectivity caused by deep-oxidation over metal oxide catalysts. Herein, we report a nonmetallic BN embedded graphitic carbon catalyst which was synthesized by a one-step co-pyrolysis method using boric acid, urea and ammonium iron citrate as the reactants. The obtained catalyst exhibits a high styrene selectivity of 94%. The existence of abundant carbonyl groups and BO species could correspondingly contribute more reaction sites and extra oxygen adsorption sites. A higher styrene formation rate of 5.8 mmol g_cat⁻¹ h⁻¹ is thus achieved for our BN embedded graphitic carbon catalyst, whereas this value is 3.4 mmol g_cat⁻¹ h⁻¹ for sole carbon nanotubes and 0.2 mmol g_cat⁻¹ h⁻¹ for BN. Such promoted reactivity for oxidative dehydrogenation of ethylbenzene is derived from the synergetic and collaborative effect of the nonmetallic BN and graphitic carbon catalyst.