Partial Hydrogenation Of Benzene To Cyclohexene Over Co@Ru Core-Shell Catalyst

Cyclohexene, which possesses a highly reactive double band, could be used as an important intermediate material for producing fine chemicals. Since a route running via selective hydrogenation of benzene to cyclohexene which was firstly worked out by the Asahi chemical industry, many domestic research institutions, colleges and petrochemical corporations paid more attention to this technology. Owing to the limitation of the patent, the research of partial hydrogenation of benzene to cyclohexene was limited to the optimization of existed catalytic systems. So developing a new catalyst system with independent intellectual property rights which can be applied to partial hydrogenation of benzene is of great value to the development of polyamide and other related industries in our nation.In this paper, calculation to the Co@Ru core-shell catalyst based on the quantum chemistry theory is taken out first. The result shows that, the magnetic metal cobalt core has a significant effect on the d electronic structure of Ru shell. The d-band center of Ru ranges from-1.10eV to1.14eV as the increase of atomic layer. Which indicate that control of the hydrogenation activity over Co@Ru core-shell catalyst is available.Accordingly, Co particles range from nanometer to submicron levels are prepared through hydrazine hydrate ligand and alcohol reduction method, then active metal Ru are coated on submicron Co particles by metal reduction based on electric potential difference. Amorphous Co nanoparticles can be prepared by rapid injection method. The hexagonal crystal structure Co submicron particles can be prepared by temperature programmed polyol reduction. Ru shell coat on the submicron Co particles successfully by replacement reduction method forming Co@Ru core-shell catalyst. The Ru shell is in a state of quasicrystal when the initial mole ratio of Co to Ru is greater than6to1, the binding energy of Ru valence electron shift obviously for the existence of Co core.The reaction of partial hydrogenation of benzene over Co@Ru core-shell catalyst is taken at140℃and at5MPa H2. The result shows that, Co@Ru core-shell catalyst have selectivity to cyclohexene without the existence of ZnSO4. When n(Co):n(Ru)=9:1, the yield of cyclohexene is up to12%.