Synthesis of PVP-stabilized Pt/Ru colloidal nanoparticles by ethanol reduction and their catalytic properties for selective hydrogenation of ortho-chloronitrobenzene

• Published in: Journal of catalysis Vol. 278; no. 1; pp. 1 - 7
• Main Authors: Liu, Manhong, Zhang, Jin, Liu, Jinqiang, Yu, William W.
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier Inc 14.02.2011; Elsevier; Elsevier BV
• Subjects: Catalysis; Catalysts; Chemical synthesis; Chemistry; Colloidal state and disperse state; Ethanol reduction; Exact sciences and technology; General and physical chemistry; Hydrogenation; Nanoparticles; Ortho-chloroaniline; Ortho-chloronitrobenzene; Physical and chemical studies. Granulometry. Electrokinetic phenomena; Pt/Ru; Theory of reactions, general kinetics. Catalysis. Nomenclature, chemical documentation, computer chemistry; Nanoparticles; Ortho-chloroaniline; Pt/Ru; Ortho-chloronitrobenzene; Catalysis; Ethanol reduction; Hydrogenation; Composition; Catalytic reaction; Ethanol; Hydrogen; Nanoparticle; Alcohol; X ray; Selectivity; Conversion; Chemical reduction; Heterogeneous catalysis; Synthesis; Distribution; Alkanol; Photoelectron spectrometry; Catalyst; Diameter
• ISSN: 0021-9517; 1090-2694
• DOI: 10.1016/j.jcat.2010.11.009

PVP-Pt/Ru colloidal nanoparticles prepared by ethanol reduction exhibit high activity and high selectivity in the selective hydrogenation of ortho-chloronitrobenzene to ortho-chloroaniline under ambient conditions. TEM photographs of PVP-Pt/Ru nanoparticles: 4Pt/1Ru (left), 2Pt/1Ru (right). [Display omitted] ► Stable PVP-Pt/Ru colloidal nanoparticles were prepared by ethanol reduction. ► A quasi core–shell structure with Ru enriched in shell was verified by TEM, XPS. ► Selective hydrogenation of o-CNB to o-CAN was operated under ambient conditions. ► 99.0% selectivity to o-CAN at 100% conversion of o-CNB was achieved. ► The catalytic performance of the nanoparticles depended on their compositions. Stable poly(N-vinyl-2-pyrrolidone)-stabilized Pt/Ru colloidal nanoparticles (PVP-Pt/Ru) were prepared via ethanol reduction of H 2PtCl 6⋅6H 2O and RuCl 3⋅ nH 2O. The average diameters of the nanoparticles with different molar ratio of Pt/Ru were in a range of 2.1–2.8 nm with narrow size distributions. X-ray photoelectron spectroscopy verified that both Pt and Ru were in the metallic state and Ru was rich on the surface. These nanoparticles were employed to selectively hydrogenate ortho-chloronitrobenzene at 298 K and 0.1 MPa hydrogen pressure. They showed high activity [TOF was in the range of 0.8–5.3 × 10 −2 mol o -CNB/(mol M,surface atom) s] and high selectivity (93–99%) to ortho-chloroaniline ( o-CAN) for the reaction, which were composition-dependent. The selectivity to o-CAN monotonously increased, but the activity of the catalyst decreased with the increasing proportion of Ru in Pt/Ru colloidal catalysts. PVP-1Pt/4Ru nanoparticles exhibited the highest selectivity of 99.0% to o-CAN at a complete conversion.