Abstract:Ruthenium catalysts supported on high surface area graphite (HSAG), impregnated with KNO3 and Ba(NO3)2,was prepared via metal-organic chemical vapour deposition technology (MOCVD) with tri-ruthenium dodecacarbonyl as the Ru precursor. The catalysts were characterized by X-ray diffraction, N2 physical adsorption and transmission electron microscope. The activity of the Ru catalyst for ammonia synthesis was evaluated. The results showed that the sublimation rate of tri-ruthenium dodecacarbony depends on temperature under vacuum and dark conditions. It is confirmed that uniform dispersion can be achieved via MOCVD route with Ru nanoparticle sizes around 2 nm. As Ru3(CO)12 commences to decompose at 130 ℃ and reach maximum decomposition rate at 175 ℃, the sublimation temperature is suggested to be 110—130 ℃. With the increase in Ru loading from 3.2% to 6.0%, as evidenced by TEM experiments, Ru nanoparticle size keeps unchanged (around 2 nm), while the activity for ammonia synthesis is enhanced dramatically, especially at low temperature (375 ℃).
Yan Haiyu,Huang Shiliang,Han Wenfeng et al. Preparation of Ru/HSAG Catalysts for Ammonia Synthesis via Metal-Organic Chemical Vapour Deposition Technology[J]. 化学反应工程与工艺, 2014, 30(5): 446-451.