Cyclohexanone Conversion Catalyzed by Pt/γ-Al2O3: Evidence of Oxygen Removal and Coupling Reactions

The conversion of cyclohexanone, often identified as an intermediate in the conversion of lignin-derived compounds, was catalyzed by Pt/gamma-Al2O3 in the presence of H-2 at 573 K. Dehydrogenation was a kinetically significant reaction, indicated by a high selectivity for phenol. Oxygen-removal reactions are indicated by products including benzene, cyclohexene, and cyclohexene. Bimolecular reactions involving cyclohexanone and/or products of its conversion led to the formation of bicyclic C-12 compounds, with 2-cyclohexylcyclohexan-1-one and 2-phenylphenol being the most abundant. Increasing the H-2 partial pressure led to increased oxygen removal and faster formation of monocyclic and bicyclic hydrocarbons. At temperatures higher than 573 K, dehydrogenation became the dominant reaction class.