The hydrogenation of phenol is an important reaction in the chemical industry, particularly for the sustainable production of cyclohexanol and cyclohexane—key intermediates in polymer and fuel applications. In this study, we investigate the catalytic performance of nitrogen-doped nickel supported on alumina (N-doped Ni@Al₂O₃) as a cost-effective alternative to conventional precious metal catalysts such as palladium and platinum. A series of catalysts with different Ni weight percentages (0.1-5wt%) were studied and evaluated for activity and selectivity under identical hydrogenation conditions. Our findings reveal a distinct trend: reducing Ni loading enhances selectivity toward cyclohexane, while higher loadings favor cyclohexanol formation. Comparative studies with undoped Ni@Al₂O₃ demonstrate the superior performance and tunability of the N-doped variant, attributed to electronic modifications and altered hydrogen adsorption properties. These results suggest that precise control of Ni content in N-doped systems offers a strategic pathway for product selectivity without relying on expensive noble metals. It has also certain effect of size of the particles to the conversion. This work not only presents a scalable, economically viable catalyst system but also contributes to advancing the rational design of selective hydrogenation catalysts.
