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Introduction Platinum catalysts have usually been prepared by impregnating a platinum precursor on supports with exceptional thermal and mechanical stabilities to achieve a high platinum dispersion and long catalyst life [ 1

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Reaction Kinetics, Mechanisms and Catalysis
Authors: Nancy Martín, Alejandro López-Gaona, Margarita Viniegra, Patricia Villamil, and Gilberto Córdoba

Abstract  

Two mesoporous silicas (HMS) with high surface area and a pore diameter size of 2 nm were synthesized by a sol–gel method. Platinum catalysts were prepared with a 1 wt% metal content. A commercial silica supported catalyst was used for comparison. The catalysts were characterized by H2-TPR, TEM and 29Si-CP-MAS-NMR. The catalytic activity was measured by the hydrodechlorination of 1,2-dichloroethane. The enhanced activity of the mesoporous catalysts was related to the platinum particle size.

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Abstract  

Partitioning of plutonium from uranium is an important step in the reprocessing of spent fuel by PUREX process of solvent extraction using 30% TBP-dodecane. This is achieved by selectively reducing the Pu in solution to least extractable trivalent state by uranous nitrate as the reductant. The latter is conventionally produced by electrolytic reduction of uranyl ion in presence of hydrazine nitrate as uranous nitrate stabilizer using Pt-coated titanium as the anode. The anode plating wears out after period of operation thus affecting the process efficiency and hence the quality control testing of platinum plated electrode becomes important. This article describes the use of Beta backscattering method with strontium-90 radioisotope as non-destructive testing tool for measuring the coating thickness of the sample Ti electrode. The surface characteristics and coating morphology were also examined by scanning electron microscope and the micrographs are presented.

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, loaded with rare earth elements and platinum or solely loaded with platinum. The catalytic results obtained in n -hexane hydroisomerization are analyzed regarding the three independent pore systems of MCM-22 zeolite, discussing the influence of RE

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component for dehydrogenation/hydrogenation provided by a noble metal, basically platinum or palladium [ 1 , 2 ] and an acid function generated by zeolites like mordenite and ZSM-5 for isomerisation/cracking [ 3 , 4 ]. The hydroisomerization mechanism is

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Reaction Kinetics, Mechanisms and Catalysis
Authors: Bianca V. Sousa, Karoline D. Brito, José J. N. Alves, Meiry G. F. Rodrigues, Carlos M. N. Yoshioka, and Dilson Cardoso

the catalysis, the functions of the metallic components and hydrogen during each isomerization step [ 10 ]. Highly chlorinated platinum-alumina catalysts can be used at low temperatures (120–180 °C). However, these catalysts are very sensitive

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Some features of DTA in platinum crucibles in air related to the catalytic activity of platinum in many oxidation reactions have been considered. This property of platinum should be taken into account in the interpretation of the DTA curves.

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composition necessary for kinetic analysis can be simultaneously monitored. The new technique has been applied to investigate the kinetics of methane combustion over platinum in the pressure range 4–16 bar [ 7 ], to identify the impact of large exhaust gas

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opportunity to tailor both the size and the composition of the metal catalyst, which seems independent of the support [ 11 , 16 ]. Supported platinum catalysts have been most intensively used in catalytic reactions, such as hydrogenation of

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washing electrochemical cell (10 mL) to allow matrix solution exchange were used. A Pt–20% Rh foil (3 mm × 12.5 mm × 60 μm) was used as working electrode. A large platinum gauze (around 1 cm 2 ) (Heraeus Vectra) was the counter-electrode and an Ag

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