Palladium Catalysts
Mostrando 1-12 de 37 artigos, teses e dissertações.
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1. Influence of the Capping Agent PVP of the Outer Layer of Pd Nanocubes Surface on the Catalytic Hydrogenation of Unsaturated C−C Bonds
The excess of capping agents used during the synthesis of nanoparticles is usually removed by solvent washing. The influence of the amount of polyvinylpyrrolidone (PVP) capping agent in the catalytic activity of palladium nanocubes was evaluated, after different numbers of washing cycles in the purification step performed after the syntheses of the nanoparti
J. Braz. Chem. Soc.. Publicado em: 2020-05
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2. MORE ACTIVE AND SULFUR RESISTANT BIMETALLIC Pd-Ni CATALYSTS
The influence of the kind of metal precursor and the sequence of impregnation on the properties of Pd-Ni catalysts was evaluated during the test reaction of selective hydrogenation of styrene to ethylbenzene by means of physicochemical characterization. The focus was put on the final hydrogenating activity and the resistance to deactivation by sulfided compo
Quím. Nova. Publicado em: 2018-02
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3. MODELING STYRENE HYDROGENATION KINETICS USING PALLADIUM CATALYSTS
Abstract The high octane number of pyrolysis gasoline (PYGAS) explains its insertion in the gasoline pool. However, its use is troublesome due to the presence of gum-forming chemicals which, in turn, can be removed via hydrogenation. The use of Langmuir-Hinshelwood kinetic models was evaluated for hydrogenation of styrene, a typical gum monomer, using Pd/9%N
Braz. J. Chem. Eng.. Publicado em: 2016-09
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4. Effect of Metal Dispersion on the Hydrogenation of 2-Amyl Anthraquinone over Pd/Al2O3 Catalyst
A series of highly dispersed Pd/Al2O3 catalysts were prepared via the polyol method. The catalysts were characterized by nitrogen adsorption, X-ray diffraction (XRD), UV-Vis spectrophotometry, temperature programmed reduction (TPR) and transmission electron microscopy (TEM). The influence of Pd particle size on the hydrogenation of 2-amyl anthraquinone (AAQ)
J. Braz. Chem. Soc.. Publicado em: 2016-06
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5. Zwitterionic Surfactant Stabilized Palladium Nanoparticles as Catalysts in Aromatic Nitro Compound Reductions
Palladium nanoparticles (NPs) stabilized by ImS3-14, a zwitterionic surfactant structurally related to ionic liquids, are revealed here to be good catalysts for the reduction of a large number of substituted aromatic nitro compounds. Our mass spectrometry results are consistent with the formation of amino products in a direct route, where the aromatic nitro
J. Braz. Chem. Soc.. Publicado em: 2016-02
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6. Desenvolvimento de reator tipo "dip catalyst" para filmes poliméricos contendo nanopartículas de metais de transição
This article describes the development of a new catalytic reactor designed to operate with nanoparticle-embedded polymer thin films. Stabilization of metal nanoparticles in films that serve as catalysts in organic reactions is relatively new; therefore, the development of reactors to facilitate their use is necessary. We describe in detail the preparation of
Quím. Nova. Publicado em: 2014
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7. Textural properties of nickel, palladium and titanium oxides supported on MCM-41 materials and their application on oxidative desulfurization of dibenzothiophene
Textural and catalytic properties of nickel, palladium or titanium oxides supported on MCM-41 materials were evaluated in this paper. The results indicated that the MCM-41 material with well defined and highly ordered hexagonal structure was obtained. After metal ions impregnation and calcinations, the structure of MCM-41 was preserved and formed metallic ox
Mat. Res.. Publicado em: 27/09/2013
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8. Síntese, caracterização e atividade fotocatalítica de catalisadores nanoestruturados de TiO2 dopados com metais
Titanium dioxide nanostructured catalysts (nanotubes) doped with different metals (silver, gold, copper, palladium and zinc) were synthesized by the hydrothermal method in order to promote an increase in their photocatalytic activity under visible light. The catalysts were characterized by X-ray diffraction, diffuse reflectance spectroscopy, transmission ele
Quím. Nova. Publicado em: 2013
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9. Palladium-supported catalysts in methane combustion: comparison of alumina and zirconia supports
Palladium catalysts supported on alumina and zirconia were prepared by the impregnation method and calcined at 600 and 1000 ºC. Catalysts were characterized by BET measurements, XRD, XPS, O2-TPD and tested in methane combustion through temperature programmed surface reaction. Alumina supported catalysts were slightly more active than zirconia supported cata
Química Nova. Publicado em: 2012
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10. O efeito da desativação térmica nas propriedades oxirredutoras e na atividade catalítica de catalisadores CZ e Pd-CZ
Automotive catalyst, using in Brazil since 1992, is a essential technology for vehicular emissions control. Noble metals are the active phase of these catalysts, and cerium zirconium mixed oxides (CZ), responsibles for the oxygen storage capacity (OSC), one of the most important aspect for the operational performance of the catalyst. In this context, the oxi
Química Nova. Publicado em: 2012
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11. Catalisadores de paládio suportado em carvão ativado para produção de biocombustíveis / Palladium catalysts supported on activated carbon for the production of biofuels.
A proposta deste trabalho é estudar a preparação e caracterização do catalisador Pd/C para a descarboxilação do ácido esteárico, a fim de obter biodiesel parafínico. Os precursores utilizados na preparação dos carvões foram o endocarpo do coco da baía e a bainha da palmeira de manila. Estes carvões foram ativados quimicamente e por microondas
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 16/11/2011
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12. Activity and sulfur resistance of Rh(I) and Pd(II) complexes
Two complexes of Rh(I) and Pd(II) with chloride and tridecylamine ligands were obtained and characterized by Elementary Analysis and by XPS and FTIR spectroscopies. Complexes anchored on γ-Al2O3 were tested in the styrene semi-hydrogenation reaction carried out in the absence or presence of a sulfur poison. Although both low loaded catalysts were highly sel
Química Nova. Publicado em: 2011