Interaction of Anisole on Alumina-Supported Ni and Mo Oxide Hydrodeoxygenation Catalysts
(2023) In Journal of Physical Chemistry C 127(39). p.19440-19450- Abstract
The conversion of biomass to transportation fuels and value-added chemicals is a promising method to reduce the reliance on fossil fuels. Mo-based catalysts have been shown to be highly active in the hydrodeoxygenation of biomass-derived phenolic compounds. The catalyst active phase, surface species, and the effect of adding additional metals are not comprehensively understood. Here we compare the temperature-dependent adsorption behavior of the model compound anisole on an alumina-supported mixed nickel molybdenum oxide catalyst with two reference catalysts, molybdenum oxide and nickel oxide. Raman spectroscopy showed that the catalysts contain significant amounts of molybdates and molybdoaluminates, in addition to NiMoO4 in... (More)
The conversion of biomass to transportation fuels and value-added chemicals is a promising method to reduce the reliance on fossil fuels. Mo-based catalysts have been shown to be highly active in the hydrodeoxygenation of biomass-derived phenolic compounds. The catalyst active phase, surface species, and the effect of adding additional metals are not comprehensively understood. Here we compare the temperature-dependent adsorption behavior of the model compound anisole on an alumina-supported mixed nickel molybdenum oxide catalyst with two reference catalysts, molybdenum oxide and nickel oxide. Raman spectroscopy showed that the catalysts contain significant amounts of molybdates and molybdoaluminates, in addition to NiMoO4 in the nickel molybdenum catalyst and MoO3 in the molybdenum-only catalyst. Using transmission infrared spectroscopy under a controlled environment, we find that anisole chemisorbed largely through the oxygen in the methoxy group to form surface-bound phenoxy and methoxy species on all of the catalysts. Ambient pressure X-ray photoelectron spectroscopy measurements of the catalysts in anisole vapor showed reduced Mo atoms are the binding sites. The surface interaction and removal temperature of these species varied with the metal composition. The MoOx component dominated the adsorption behavior in both MoOx and NiMoOx catalysts. The formation of new aromatics, including methylated rings, depended on the Ni composition. Upon the addition of hydrogen to induce the hydrodeoxygenation of anisole, undesirable polynuclear aromatic species were quickly formed on the Mo-based catalysts. These results suggest that the molybdenum oxide controls the adsorption and reactivity of the surface species with a cooperative effect by Ni.
(Less)
- author
- Hu, Tianhao ; Gericke, Sabrina M. LU ; Tong, Xiao ; Nykypanchuk, Dmytro ; Kristensen, Tove LU ; Hulteberg, Christian LU ; Stacchiola, Dario ; Blomberg, Sara LU and Head, Ashley R. LU
- organization
- publishing date
- 2023
- type
- Contribution to journal
- publication status
- published
- subject
- in
- Journal of Physical Chemistry C
- volume
- 127
- issue
- 39
- pages
- 19440 - 19450
- publisher
- The American Chemical Society (ACS)
- external identifiers
-
- scopus:85175304215
- ISSN
- 1932-7447
- DOI
- 10.1021/acs.jpcc.3c02780
- language
- English
- LU publication?
- yes
- id
- 4b403560-18e5-47c1-b522-d16e79e5445f
- date added to LUP
- 2023-11-16 09:54:01
- date last changed
- 2024-04-15 12:06:09
@article{4b403560-18e5-47c1-b522-d16e79e5445f, abstract = {{<p>The conversion of biomass to transportation fuels and value-added chemicals is a promising method to reduce the reliance on fossil fuels. Mo-based catalysts have been shown to be highly active in the hydrodeoxygenation of biomass-derived phenolic compounds. The catalyst active phase, surface species, and the effect of adding additional metals are not comprehensively understood. Here we compare the temperature-dependent adsorption behavior of the model compound anisole on an alumina-supported mixed nickel molybdenum oxide catalyst with two reference catalysts, molybdenum oxide and nickel oxide. Raman spectroscopy showed that the catalysts contain significant amounts of molybdates and molybdoaluminates, in addition to NiMoO<sub>4</sub> in the nickel molybdenum catalyst and MoO<sub>3</sub> in the molybdenum-only catalyst. Using transmission infrared spectroscopy under a controlled environment, we find that anisole chemisorbed largely through the oxygen in the methoxy group to form surface-bound phenoxy and methoxy species on all of the catalysts. Ambient pressure X-ray photoelectron spectroscopy measurements of the catalysts in anisole vapor showed reduced Mo atoms are the binding sites. The surface interaction and removal temperature of these species varied with the metal composition. The MoO<sub>x</sub> component dominated the adsorption behavior in both MoO<sub>x</sub> and NiMoO<sub>x</sub> catalysts. The formation of new aromatics, including methylated rings, depended on the Ni composition. Upon the addition of hydrogen to induce the hydrodeoxygenation of anisole, undesirable polynuclear aromatic species were quickly formed on the Mo-based catalysts. These results suggest that the molybdenum oxide controls the adsorption and reactivity of the surface species with a cooperative effect by Ni.</p>}}, author = {{Hu, Tianhao and Gericke, Sabrina M. and Tong, Xiao and Nykypanchuk, Dmytro and Kristensen, Tove and Hulteberg, Christian and Stacchiola, Dario and Blomberg, Sara and Head, Ashley R.}}, issn = {{1932-7447}}, language = {{eng}}, number = {{39}}, pages = {{19440--19450}}, publisher = {{The American Chemical Society (ACS)}}, series = {{Journal of Physical Chemistry C}}, title = {{Interaction of Anisole on Alumina-Supported Ni and Mo Oxide Hydrodeoxygenation Catalysts}}, url = {{http://dx.doi.org/10.1021/acs.jpcc.3c02780}}, doi = {{10.1021/acs.jpcc.3c02780}}, volume = {{127}}, year = {{2023}}, }