High Performance of Palladium Nanoparticles Supported on Carbon Nanotubes for the Hydrogenation of Commercial Polystyrene

Mechanism of NCNTs Growth on Foamed Nickel and Thus-Prepared PS Hydrogenation High-Performance Carrier NCNTs@FN

Traditional heterogeneous catalysts are affected in the catalytic hydrogenation of PS by the scale effect, viscosity effect, adhesion effect, and conformational effect, resulting in poor activity and stability. Monolithic Pd-CNTs@FN catalysts could eliminate or weaken the impact of these negative effects. We grew nitrogen-doped carbon nanotubes (NCNTs) on monolithic-foamed nickel (FN) and investigate their growth mechanism. Meanwhile, the feasibility of using the NCNTs@FN carrier for PS hydrogenation reaction was also verified. The growth of NCNTs on FN can be divided into 3 stages: initial growth stage, stable growth stage, and supersaturation stage. Finally, a three-layer structure of NCNT layer, dense carbon layer, and FN skeleton is formed. Two types of structures, nickel-doped carbon nanotubes (NiCNTs) and C-Ni alloy, are formed by combining C and Ni, while four nitrogen-doped structures, NPD, NPR, NG, and NO, are formed by C and N. The prepared carrier exhibited an extremely outstanding specific surface area (2.829 × 106 cm2/g) and strength (no NCNTs falling off after 24 h 500 rpm agitation), as well as high catalytic activity for PS hydrogenation after loaded with Pd (2.13 ± 0.95 nm), with a TOF of up to 27.6 gPS/(gPd•h). After 8 repetitions of the catalyst, there was no significant decrease in activity. This proves the excellent performance of Pd-NCNTs@FN in polymer hydrogenation reactions, laying a solid foundation for further research on the mechanism of NCNTs promoting PS hydrogenation and regulating the growth of NCNTs.

Nanosized palladium on phosphorus-incorporated porous carbon frameworks for enhanced selective phenylacetylene hydrogenation

In the present study, Pd nanoparticles supported on phosphorus-incorporated porous carbon frameworks were prepared and used in selective phenylacetylene hydrogenation.

Graphene-supported Pd catalyst for highly selective hydrogenation of resorcinol to 1, 3-cyclohexanedione through giant π-conjugate interactions

The selective hydrogenation of resorcinol (RES) to 1, 3-cyclohexanedione (1,3-CHD) without the addition of alkali is a big challenge. In this article, a novel reduced graphene oxide (rGO) supported Pd catalyst was prepared through co-reduction method, over which we obtained 99.9% of resorcinol conversion and 94.2% of the ever-reported highest 1,3-cyclohexanedione selectivity at 25 °C in only CH₂Cl₂ solvent. The excellent selectivity was contributed to the strong π-π and p-π interactions between the graphene nanosheet and the benzene ring as well as hydroxyl in RES molecule. The followed adsorption experiment and Raman analysis also showed the existence of aromatic graphite structures in rGO, which exhibited stronger adsorption towards RES than towards 1,3-CHD.

Enhanced catalytic properties of rhodium nanoparticles deposited on chemically modified SiO2 for hydrogenation of nitrile butadiene rubber

Rh NPs deposited on chemical modified SiO₂ is an effective, selective and recyclable catalyst for hydrogenation of nitrile butadiene rubber.

Carbon nanotube catalysts: recent advances in synthesis, characterization and applications

Carbon nanotubes are promising materials for various applications.

One-step fabrication of RGO/HNBR composites via selective hydrogenation of NBR with graphene-based catalyst

Enhanced mechanical and electrical RGO/HNBR composite was prepared by hydrogenation of NBR with grapheme-based catalyst.