Gas‐Phase Hydrodeoxygenation of m‐Cresol Using Isopropanol as Hydrogen Donor Over a Ni‐Supported Catalyst

ABSTRACT This work explored the potential of the hydrodeoxygenation process assisted by catalytic transfer hydrogenation (CTH‐HDO) as an alternative to the conventional hydrotreatment process that relies on high‐pressure molecular hydrogen. Gas‐phase CTH‐HDO of m‐cresol was studied over a series of metals (Pt, Pd, Ru, Cu, Ni, Fe, Co) supported on SBA‐15 catalysts under atmospheric pressure with isopropanol as H‐donor molecule. The influence of reaction parameters such as temperature and isopropanol/m‐cresol molar ratio on m‐cresol conversion and product selectivity was examined. Well‐dispersed Ni nanoparticles confined within the SBA‐15 framework presented better activity, efficiently promoting isopropanol dehydrogenation, with 97 % selectivity toward H 2 and acetone, while simultaneously enabling the deoxygenation of m‐cresol to toluene (56 %) at optimized reaction conditions (T = 350 °C, isopropanol/m‐cresol molar ratio = 3/1). However, a significant formation of xylenols (28 %) was observed, resulting from the C─C bond cleavage of isopropanol followed by alkylation of m‐cresol, attributed to the intrinsic hydrogenolysis activity of Ni. These results demonstrate the potential of CTH‐HDO in continuous flow conditions using cost‐effective Ni‐based catalysts, while clearly highlighting the critical need for catalyst optimization to steer selectivity and suppress competing reaction pathways in such a complex system involving dehydrogenation, hydrogenation, deoxygenation, and hydrogenolysis reactions.