A Novel Two-Step Conversion of Lignin-Derived Phenol to Benzene Through Hydrogenation and Dehydrogenation

Arenes possess high energy density and outstanding combustion performance, making them key components of aviation fuels. However, the conversion of lignin-derived phenolic compounds to arenes typically requires high temperatures (above 300°C), which not only alters the catalyst structure and promotes side reactions but also increases energy consumption and potential safety risks. In this study, a green and environmentally friendly two-step method for the low-temperature conversion of phenol to benzene was proposed, achieving controllable product selectivity at low temperatures. The hydrogenation of phenol occurred efficiently at room temperature and achieved 100% conversion of cyclohexanol. Then, the dehydration and dehydrogenation of cyclohexanol was performed at a low temperature of 200°C, resulting in 90.1% selectivity of benzene. In addition, the catalyst showed good cycling stability, with the benzene selectivity remaining at 84.6% after four reaction cycles. Based on the effect of reaction time on product distribution, a proposed reaction pathway for cyclohexanol to benzene was discussed. Moreover, the comparison between this two-step method and previously reported one-step methods for phenol to benzene was carried out, highlighting the superiority of this work.