Bifunctional transalkylation and hydrodeoxygenation of anisole over a Pt/HBeta catalyst

The catalytic conversion of anisole (methoxybenzene), a phenolic model compound representing a thermal conversion product of biomass lignin, to gasoline-range molecules has been investigated over a bifunctional Pt/HBeta catalyst at 400 °C and atmospheric pressure. The product distribution obtained on the bifunctional catalyst was compared with those obtained on monofunctional catalysts (HBeta and Pt/SiO2). This comparison indicates that the acidic function (HBeta) catalyzes the methyl transfer reaction (transalkylation) from methoxyl to the phenolic ring, yielding phenol, cresols, and xylenols as the major products. The metal function catalyzes demethylation, hydrodeoxygenation, and hydrogenation in sequence, resulting in phenol, benzene, and cyclohexane. On the bifunctional catalyst, both methyl transfer and hydrodeoxygenation are achieved at significantly higher rates than over the monofunctional catalysts, leading to the formation of benzene, toluene, and xylenes with lower hydrogen consumption and a significant reduction in carbon losses, in comparison with the metal function alone. In addition, on the bifunctional Pt/HBeta, the rate of deactivation and coke deposition are moderately reduced.

Conversion of anisole (methoxybenzene), a biomass-derived phenolic model compound, to benzene, toluene, and xylenes has been achieved over a bifunctional Pt/HBeta catalyst that catalyzes both transalkylation and hydrodeoxygenation reactions. Concerted (bifunctional) participation of acid site and metal sites in both reactions is postulated.Figure optionsDownload high-quality image (76 K)Download as PowerPoint slideHighlights
► Conversion of anisole has been studied over bifunctional Pt/HBeta at 400 °C and 1 atm.
► Anisole is a phenolic model compound representing a thermal conversion product of biomass lignin.
► Acid catalyzes methyl transfer, while metal catalyzes demethylation and hydrodeoxygenation.
► On bifunctional Pt/HBeta catalyst, a synergism is observed, resulting in uniquely high activity.