Directing nitrogen-doped carbon support chemistry for improved aqueous phase hydrogenation catalysis
| Autor: | Lina Rustam, Anna Fischer, Robin J. White, Ralf Thomann, Monika Bosilj, Julia Melke |
|---|---|
| Rok vydání: | 2020 |
| Předmět: |
Carbonization
chemistry.chemical_element Cyclohexanone Context (language use) 02 engineering and technology 010402 general chemistry 021001 nanoscience & nanotechnology 01 natural sciences Catalysis Nanomaterial-based catalyst 0104 chemical sciences chemistry.chemical_compound chemistry Chemical engineering Hydrothermal synthesis 0210 nano-technology Selectivity Palladium |
| Zdroj: | Catalysis Science & Technology. 10:4794-4808 |
| ISSN: | 2044-4761 2044-4753 |
| Popis: | Selective hydrogenations in the aqueous phase are an important transformation in the context of developing biorefinery concepts. In this report the application and optimisation of nitrogen-doped carbon (NDC) supported Pd nanoparticles as hydrogenation catalysts is discussed in the context of directing support (e.g. N) chemistry for improved catalytic performance in the aqueous phase. As a demonstrative example, the aqueous phase hydrogenation of phenol to cyclohexanone (e.g. a platform for polyamide production) is utilised. Catalyst supports were prepared based on an initial hydrothermal synthesis to yield NDC xerogels (from biomass precursors), the chemistry of which (e.g. functionality) was directed using a secondary thermal carbonisation (Tc) step at different temperatures (i.e. 350, 550, 750, 900 and 1000 °C). After Pd introduction, it was found that size, dispersion and electronic structure of the formed nanoparticles is affected by the surface chemistry of the NDC. This consequently led to higher turn-over frequency (TOF) and stability of the prepared catalysts compared to a “nitrogen-free” carbon supported Pd and a commercial, carbon supported Pd (Pd/AC) catalyst. Pd/NDC 900 (featuring predominantly quaternary and pyridinic N) catalysed the complete conversion of phenol at 99% selectivity to cyclohexanone, with excellent stability over 11 recycles and no discernible catalyst sintering or leaching (in contrast to the commercial catalyst). High catalytic stability, activity and selectivity make the Pd/NDC 900 catalyst highly applicable for aqueous phase hydrogenation reactions, whilst the general principle opens scope for support tailoring for application (e.g. biorefinery hydrogenations) and the development of structure/activity relationships. |
| Databáze: | OpenAIRE |
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