Study On The Surface Characteristics Of Nano-Magnesium Doped Barium Prapared By Template Method And Its Supported Ru-based Catalysts For Ammonia Synthesis

Different materials,i.e.,rice,ordered mesoporous carbon?OMC?and coconut shell activated carbon?N-AC?were used as templates to prepare nano-magnesia doped barium and its supported Ru-based catalysts for ammonia synthesis.The surface characteristics of nano-magnesium doped barium with high surface area and the adsorption property of H₂ of its supported Ru-based catalysts for ammonia synthesis were investigated by Field emission scanning electron microscopy?FE-SEM?,Energy dispersive X-ray?EDS?,X-ray diffraction?XRD?,N₂ physical-adsorption,Thermo gravimetric?TG/DTG?,Temperature-programmed desorption?TPD?,etc.The main research contents and results were as follows:1.The prepared nano-magnesia doped barium complete copy out special shape and structure of the templates.Finally found,the prepared nano-magnesia doped barium using OMC as template not only has high surface area?103 m²/g?but has orderd structure through a series of optimization of preparation conditions.And the activity of its supported Ru-based catalysts for ammonia synthesis was 66.09mmol·g^-1·h^-1?Reaction rate?under the reaction condition of 10 MPa,425^oC and 10000 h^-1.This reaction rate was equivalent to the rate of Ru/Ba-MgO catalysts prepared by ultrasound-precipitation-strong electrical adsorption?SEA?method(63.45 mmol·g^-1·h^-1).2.The surface characteristics of nano-Ba-MgO,prepared by different templates?rice,OMC and N-AC?or methods?template method and SEA method?,and its supported Ru-based catalysts for ammonia synthesis were studied by temperature programmed desorption method?TPD?.The results showed that the Ba-MgO support prepared by OMC template has stronger alkalinity and its supported Ru/Ba-MgO-OMC catalyst for moderate hydrogen also has stronger adsorption property of H₂.Therefore,the reaction rate of Ru/Ba-MgO catalysts prepared by OMC template was equivalent to the rate of Ru/Ba-MgO catalysts prepared by SEA method.3.To reach higher activity of Ru/Ba-MgO catalysts for ammonia synthesis,effective and high surface area of Ba-MgO support is necessary.But suitable pore structure and excellent surface properties are more important.