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Pt/Al2O3 catalyst was prepared from a cetyltrimethylammonium bromide (CTAB)/n-butanol/cyclohexane water-in-oil (w/o) microemulsion. The preparation conditions of Pt/Al2O3 catalyst were investigated and are discussed in detail. Transmission electron microscopy (TEM) showed uniform Pt nanoparticles (about 3 nm) with high dispersion in the catalyst. The Pt/Al2O3 catalyst exhibited excellent catalytic properties in the liquid-phase hydrogenation of o-chloronitrobenzene (o-CNB) to o-chloroaniline (o-CAN). After 60-min reaction at normal pressure and 303 K, the conversion of o-CNB was 81.1% and the selectivity to o-CAN was 96.2%. Kinetic study showed o-CNB hydrogenation to be a first-order reaction with an apparent activation energy of 56.37 kJ mol-1. The microemulsion-derived catalyst shows a higher catalytic activity than an impregnation-drived catalyst. [ABSTRACT FROM AUTHOR]

[Display omitted] The fabrication of stable and efficient catalysts for green and economic catalytic transformation is significant. Here, highly stable covalent triazine frameworks (CTF-1) were used as the supporting material for anchoring ultrafine Pd nanoparticles (NPs) via a facile impregnation process and a one-pot calcination-reduction strategy. The widespread dispersion of ultrafine Pd NPs was a result of the abundant high nitrogen-content triazine groups of CTF-1 that endowed the catalyst Pd@CTF-1 with high catalytic activity. The catalytic performance of Pd@CTF-1 was demonstrated by the one-pot N -alkylation of benzaldehyde with aniline (or nitrobenzene) under mild reaction conditions, and Pd@CTF-1 exhibited a wide range of general applicability for N -alkylation reactions. The reaction mechanism for the N -alkylation reaction was also studied in detail. In addition, the Pd@CTF-1 catalyst exhibited high thermal and chemical stability, maintaining good catalytic efficiency after multiple reaction cycles. This study provides new insights for the fabrication of organic supporting materials with highly dispersed active catalytic sites that can lead to excellent catalytic performance for efficient, economical, and green reactions. [ABSTRACT FROM AUTHOR]

The article cites a study by researcher R.V. Jagadeesh et al. on the general synthesis of amines through reductive amination of carbonyl compounds. The researchers use a cobalt nanoparticle catalyst with a structure derived from the pyrolysis of a metal-organic framework (MOF) compound. The catalysts are vital because of their high activities and selectivities.

• MgO-decorated ZrO 2 nanoparticles were utilized to support Ru0 nanoparticles. • The formation of Mg-O-Zr structures favored the enhanced basicity of MgO-ZrO 2 support. • The enhanced hydrodeoxygenation of guaiacol was achieved by the introduction of MgO. • Ru0 sites together with basic sites contributed to the high efficiency. Presently, it is well-recognized that surface acidic sites on supported metal catalysts play an important role in promoting the hydrodeoxygenation (HDO) of lignin-derived phenolic compounds. In the present work, new insights into the promotion role of surface basic sites on the catalytic performance of MgO-decorated nanostructured ZrO 2 supported Ru nanocatalysts in the HDO of guaiacol were attained. It was found that the adsorption capacity of guaiacol and the HDO ability increased with the density of surface basic sites on as-modified Ru-based catalysts. Combining surface-interface microstructural characterizations of Ru-based catalysts and catalytic testing results with in-situ diffused reflectance infrared Fourier transform spectroscopy of guaiacol adsorption, it was unveiled that surface basic sites induced by the introduction of MgO on the ZrO 2 surface could favor the preferential adsorption of guaiacol through the hydroxyl group interacting with surface basic sites and thus simultaneously the indirect activation of the C ring -OCH 3 bond, thereby boosting the guaiacol HDO to produce cyclohexanol via the demethoxylation and following ring-hydrogenation processes. The present study may provide a promising strategy to design next generation supported metal catalysts with the improved surface basicity for the HDO of lignocellulose-derived phenolic derivates. [Display omitted] [ABSTRACT FROM AUTHOR]

A three-dimensional ordered macroporous Co 3 O 4 (OM-Co 3 O 4) supported Ru catalyst was developed for the efficient hydrodeoxygenation (HDO) of anisole. It is revealed that small-sized Ru nanoparticles evenly distributed over the surface of OM-Co 3 O 4 with large quantities of oxygen vacancies could strongly capture Ru0 species, thereby resulting in strong Ru-Co 3 O 4 interactions. Compared with commercial Co 3 O 4 supported Ru catalyst, Ru/OM-Co 3 O 4 displays a better catalytic HDO performance, with a high cyclohexane yield of 92.4% at 250 °C and 0.5 MPa hydrogen pressure after 5 h on stream. Such a significant efficiency of Ru/OM-Co 3 O 4 is mainly attributed to both high dispersion of Ru0 species and an enhanced formation of surface defects, as well as the unique macroporous framework of OM-Co 3 O 4 support. [Display omitted] • Ordered macroporous Co 3 O 4 supported Ru catalyst was constructed. • Such Ru-based nanocatalyst was highly active for the hydrodeoxygenation of anisole. • Macroporous Co 3 O 4 facilitated the formation of highly dispersed Ru nanoparticles. • Highly dispersion Ru NPs together with surface defects and macroporous framework contributed to high efficiency. [ABSTRACT FROM AUTHOR]