碳化钼负载Ru基催化剂的5-硝基苯并噻唑加氢性能研究OA北大核心

When the supported metal catalyst is used to catalyze the hydrogenation of sulfur-containing substrates,the activity of the catalyst can be deteriorated or even completely deactivated due to the strong adsorption of sulfur on the metal surface.Ru-based catalysts(Ru/α-MoC and Ru/β-Mo2C)supported by molybdenum carbide with different crystalline phases were prepared by over volume impregnation method and used to catalyze 5-nitrobenzothiazole(5-NBT)hydrogenation.The catalysts were characterized by SEM,XRD,HR-TEM and XPS,etc.The results show that the Ru loaded on α-MoC is atomically dispersed,while the Ru loaded on β-Mo2C is dispersed in the form of nanoparticles.Under the conditions of 80 ℃,2.0 MPa H2,3 mL ethanol,10 mg substrate and 10 mg catalyst,the 5-NBT hydrogenation rate of Ru/α-MoC is 9113 μmol/(g·h)when the 5-NBT conversion rate is lower than 30％.After reaction for 40 min,the 5-NBT conversion rate of Ru/α-MoC is 100％.The result of hydrogen-deium exchange experiment confirms that α-MoC plays an important role in the activation(adsorption activation)of 5-NBT nitro group,while Ru promotes H2 dissociation.The synergistic effect of these two effects makes Ru/α-MoC show relatively higher catalytic performance in 5-NBT hydrogenation.