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Conversion of m-cresol was studied on a Pt/HBeta catalyst at 225-350 °C and ambient hydrogen pressure. At 250 °C, the reaction proceeds through two major reaction pathways: (1) direct deoxygenation to toluene (DDO path); (2) hydrogenation of m-cresol to methylcyclohexanone and methylcyclohexanol on Pt, followed by fast dehydration on Brønsted acid sites (BAS) to methylcyclohexene, which is either hydrogenated to methylcyclohexane on Pt or ring-contracted to dimethylcyclopentanes and ethylcyclopentane on BAS (HYD path). The initial hydrogenation is the rate-determining step of the HYD path as its rate is significantly lower than those of subsequent steps. The apparent activation energy of the DDO path is 49.7 kJ mol−1 but the activation energy is negative for the HYD path. Therefore, higher temperatures lead to the DDO path becoming the dominant path to toluene, whereas the HYD path, followed by fast equilibration to toluene, is less dominant, owing to the inhibition of the initial hydrogenation of m-cresol. [ABSTRACT FROM AUTHOR]

The Cover shows the major reaction pathways of hydrodeoxygenation of m‐cresol to hydrocarbons on a bifunctional Pt/HBeta catalyst, consisting of both metal site (Pt) and Brønsted acid site (BAS). In their Full Paper, Sun et al. demonstrate that the reaction proceeds through both a direct deoxygenation path (DDO) to toluene and a hydrogenation‐deoxygenation path (HYD) to methylcyclohexane and ring contraction products. The selectivity between the two paths depends on competition between the initial rates of deoxygenation and hydrogenation of cresol. The apparent activation energy is positive for the DDO path, whereas it becomes negative for the HYD path. More information can be found in the Full Paper by Sun et al. on page 551 in Issue 3, 2016 (DOI: 10.1002/cctc.201501232). [ABSTRACT FROM AUTHOR]