Catalysts based on Ru/mesoporous phosphate heterostructures (PPH) for hydrotreating of aromatic hydrocarbons

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• 作者：D. Eliche-Quesada ; M.I. Mací ; as-Ortiz ; J. Jimé ; nez-Jimé ; nez ; E. Rodrí ; guez-Castelló ; n and A. Jimé ; nez-Ló ; pez
• 关键词：Mesoporous phosphate heterostructure (PPH) ; Ruthenium catalysts ; Tetralin hydrogenation ; Hydrogenolysis/hydrocracking ; Sulphur tolerance
• 刊名：Journal of Molecular Catalysis A: Chemical
• 出版年：2006
• 出版时间：1 August 2006
• 年：2006
• 卷：255
• 期：1-2
• 页码：41-48
• 全文大小：329 K

文摘

Mesoporous phosphate heterostructure (PPH) materials have been used as supports of ruthenium catalysts with a 5 wt. % metal content. A pristine support (SiPPH) was used, consisting of expanded zirconium phosphate with silica galleries and a potassium exchanged material (denoted as KSiPPH) which was prepared by the cationic exchange of the pristine support to reduce its original acidity by 20 % . Ruthenium supported on both SiPPH and KSiPPH was obtained by incipient wetness impregnation using an aqueous solution of ruthenium(III) chloride and reduction at 400 °C without previous calcination. These catalysts were assayed in the hydrogenation and hydrogenolysis/hydrocracking of tetralin at different temperatures. They show a similar catalytic performance although the 5Ru-SiPPH catalyst displays better activity at 350 °C, giving 95 % conversion in the steady-state and a very good balance between yields of hydrogenation (55 % ) and hydrogenolyis/hydrocracking products (28 % ). This better performance could be due to its better metallic properties and greater acidity. In addition, the performance of the best catalyst was studied for thiotolerance with a feed containing dibenzothiophene (DBT), a sulphur containing molecule, at concentrations of 300 and 600 ppm. This catalyst shows an excellent performance with 300 ppm of DBT after 6 h on-stream. The catalysts were characterized by several instrumental techniques such as X-ray diffraction (XRD), adsorption–desorption of nitrogen, temperature-programmed desorption (TPD) of NH₃, X-ray photoelectron spectroscopy (XPS), TEM and H₂ and O₂-chemisorption.