The selective hydrogenation of naphthalene (NAP) is of great significance in fields such as petroleum refining, organic liquid hydrogen storage, fine chemicals, and environmental protection. Not only is it an organic liquid hydrogen storage material with high hydrogen storage density, but in the petrochemical engineering sector, it can also be converted into light aromatic hydrocarbons with high cetane numbers through catalytic hydrogenation. To address the challenge of balancing activity and selectivity in the naphthalene hydrogenation reaction, this study involved the nitric acid modification of carbon fibres, which were then used as supports onto which metal nanoparticles were loaded. A series of Ru-Co bimetallic alloy catalysts with different metal molar ratios were prepared using a simple and versatile sol-gel method, and all samples underwent material characterisation testing. Inductively coupled plasma emission spectroscopy was employed to determine the actual elemental ratios; X-ray diffraction and X-ray photoelectron spectroscopy confirmed that all samples exhibited a single-phase hcp structure; N₂ adsorption-desorption area measurements revealed the catalysts' pore structure and specific surface area; and transmission electron microscopy results demonstrated that the alloy catalysts were characterised by nanoscale particle sizes, uniform elemental distribution and high metal dispersion. By adjusting the catalyst composition and metal ratio, highly efficient selective conversion of naphthalene to tetralin and decalin was achieved. Under conditions of room temperature, 2 MPa H₂, and a 30-minute reaction time, the decalin selectivity of Ru₄Co₁/CNFs reached 100%; whereas Ru₁Co₁/CNFs exhibited a tetralin selectivity as high as 99% under the same conditions, and even with extended reaction times, the reaction remained predominantly in the tetralin formation stage, demonstrating a significant suppression of deep hydrogenation. The key factor underlying this difference lies in the disparity in their apparent activation energies; the apparent activation energy of Ru₄Co₁/CNFs is significantly lower than that of Ru₁Co₁/CNFs. The component strategy regulates the d-band center and reaction rate, ultimately manifesting as selective hydrogenation. Furthermore, both Ru-Co catalysts exhibit good cycle stability and recoverability, providing key performance parameters for the industrial application of catalytic hydrogenation of polycyclic aromatic hydrocarbons.

Key words: Composition Control, Selective hydrogenation, Ru-Co alloy catalyst, Room-temperature catalysis, d-Band Center