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Introduction Heterogeneous catalysts are employed in 80 % of ind ustrial catalytic processes with multimetallic formulations which enhance the perfor mances of catalysts [1]. Nowadays, an increased attention has been paid to preparation... more
Introduction Heterogeneous catalysts are employed in 80 % of ind ustrial catalytic processes with multimetallic formulations which enhance the perfor mances of catalysts [1]. Nowadays, an increased attention has been paid to preparation me thods using “Controlled Surface Reactions (CSR)” [2, 3]. These catalysts are rather active an d selective in various reactions, for example in hydrocarbon transformation [3, 4]; promisingly r esult in cleaner products and safer processes producing less wastes. The full character ization of such catalysts requires a combination of physico-chemical methods with cataly tic tests. Our aim was to investigate bimetallic Pt-Ir catalysts prepared by two differen t methods, namely classical successive impregnation and by organometallic grafting [2, 4] as well as to study the effect of a third metal (Ge or Sn) added in both cases by organometal lic grafting method.
Sn was added to a 1% Rh/Al2O3 catalyst (D=75%) by controlled surface reaction of Sn(n-C4H9)4 in amounts corresponding nominally to 1/4, 1/2, 1 and 2 monolayers. The Sn/Rh ratios obtained were 0.19, 0.34, 0.60 and 0.75, respectively. The... more
Sn was added to a 1% Rh/Al2O3 catalyst (D=75%) by controlled surface reaction of Sn(n-C4H9)4 in amounts corresponding nominally to 1/4, 1/2, 1 and 2 monolayers. The Sn/Rh ratios obtained were 0.19, 0.34, 0.60 and 0.75, respectively. The Sn–Rh catalysts were characterized by H2 chemisorption, TEM, CO-FTIR, 119Sn-Mössbauer spectroscopy and in the test reaction of methylcyclopentane (MCP). Three different Sn
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Research Interests: Environmental Engineering, Chemical Engineering, Physics, Materials Science, Chemistry, and 10 moreHigh Pressure, Catalysis, Nanotechnology, High Resolution Transmission Electron Microscopy, Nanoscience, Palladium, Carbon Deposition, Selective Hydrogenation, HRTEM, and X Ray Photoelectron Spectroscopy
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ABSTRACT Ge–Rh/Al2O3 catalysts were prepared by organometallic grafting, with nominal Ge loadings of 1/8, 1/4, 1/2 and 1 monolayer and actual loading of 300, 600, 2000 and 2100ppm. The dispersion decreased proportionally to the Ge loading... more
ABSTRACT Ge–Rh/Al2O3 catalysts were prepared by organometallic grafting, with nominal Ge loadings of 1/8, 1/4, 1/2 and 1 monolayer and actual loading of 300, 600, 2000 and 2100ppm. The dispersion decreased proportionally to the Ge loading up to 600ppm Ge. Methylcyclopentane was used as catalytic test reaction. The selectivity of ring opening was 70–90%. Addition of 300 and 600ppm Ge divided the contiguous Rh sites to smaller ensembles. Here mostly 2-methylpentane gave C1–C5 fragments, its surface intermediate undergoing fragmentation without desorption, like on Rh with D
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... 1. Introduction. Exchanging the interlayered cations of the montmorillonite layered clay minerals for other inorganic species originates pillared montmorillonite materials. ... Its exchange capacity is 93 mequiv./100 g of clay. 2.2.... more
... 1. Introduction. Exchanging the interlayered cations of the montmorillonite layered clay minerals for other inorganic species originates pillared montmorillonite materials. ... Its exchange capacity is 93 mequiv./100 g of clay. 2.2. Synthesis. 2.2.1. Preparation of the pillaring agent. ...