aalto1 untyped-item.component.html
Hydrodeoxygenation of lignocellulose-related compounds with supported noble-metal catalysts
Loading...
URL
Journal Title
Journal ISSN
Volume Title
School of Chemical Engineering |
Doctoral thesis (article-based)
| Defence date: 2024-11-29
Electronic archive copy is available via Aalto Thesis Database.
Unless otherwise stated, all rights belong to the author. You may download, display and print this publication for Your own personal use. Commercial use is prohibited.
Authors
Date
Major/Subject
Mcode
Degree programme
Language
en
Pages
104 + app. 176
Series
Aalto University publication series DOCTORAL THESES, 247/2024
Abstract
Lignocellulose is a renewable feedstock that can potentially be processed in biorefineries into transportation biofuels. This work comprises two case studies representing the downstream valorization of biorefinery streams via hydrodeoxygenation (HDO). In HDO, the organic feedstock reacts with gaseous H2 in the presence of a catalyst to remove chemically bound oxygen, yielding deoxygenated products for biofuel production. The goals of the case studies were to investigate the effects of different noble-metal catalysts and of the reaction conditions on the HDO of representative compounds.
The first case study looked into the HDO of a potential biorefinery platform stream, Levulinic acid (LA) dimers. The experiments were performed in batch and solvent free. Firstly, model compound γ-nonalactone (GNL) was tested in HDO with different noble-metal (Ru, Rh, Pd, and Pt) catalysts supported on ZrO2. This study revealed that Ru/ZrO2 was the most effective of the tested catalysts at hydrocarbon production, although with the drawback of its tendency to crack carbon chains. The GNL tests also showed that hydrocarbons were promoted at higher temperatures. Therefore, the HDO of LA dimers was studied with Ru/ZrO2. The dimers had a strong tendency to react thermally, although it was clear that the catalyst promoted hydrogenation. Unfortunately, the thermal production of CO2 hindered the feeding of sufficient H2 into the batch reactor. Higher reaction temperatures resulted in more deoxygenation, but also in more CO2 formation. The hydrocarbon yields from LA dimers were low, and included saturated, unsaturated, cyclic, and aromatic hydrocarbons.
The second case study represented the upgrading of pyrolysis or liquefaction biocrudes and focused on the HDO of 4-prophylphenol to produce propylbenzene. The experiments were performed in batch and using n-C14H30 as a solvent. The tested catalysts were Pt/Nb2O5, Pt/TiO2, and Pt/ZrO2. The results indicated that the catalysts with the reducible supports (Nb2O5 and TiO2) were more selective to deoxygenated products than with the non-reducible support (ZrO2), and that the Nb2O5 catalyst was more selective to propylbenzene than the TiO2 catalyst. Thermodynamic calculations supported by experiments suggested that the effects of temperature and pressure on aromatic selectivity were strongly subject to limitations imposed by the thermodynamic equilibrium. Furthermore, the H2 pressure determines the temperature at which the equilibrium transitions from favoring a cycloalkane product (low temperature) to favoring an aromatic product (high temperature).
For future research on LA dimer HDO, it is recommended to ensure sufficient H2 availability and to target catalysts that are active at low temperatures (≤250 °C) to avoid the thermal reactions. Future research on phenolic compounds with niobia-supported catalysts could be promising; the thermodynamic equilibria should be considered.
Description
Supervising professor
Puurunen, Riikka, Assoc. Prof., Aalto University, Department of Chemical and Metallurgical Engineering, FinlandThesis advisor
Karinen, Reetta, D.Sc. (Tech.), Aalto University, Department of Chemical and Metallurgical Engineering, FinlandLindblad, Marina, D.Sc. (Tech.), Neste Corporation, Finland
Other note
Parts
- [Publication 1]: González Escobedo, José Luis*; Mäkelä, Eveliina*; Braunschweiler, Aki; Lehtonen, Juha; Lindblad, Marina; Puurunen, Riikka L.; Karinen, Reetta. 2019. * These authors contributed equally. Solvent-free Hydrodeoxygenation of γ-Nonalactone on Noble Metal Catalysts Supported on Zirconia. Topics in Catalysis, volume 62, issue 7–11, pages 724–737.
Full text in Acris/Aaltodoc: https://urn.fi/URN:NBN:fi:aalto-201905062870
- [Publication 2]: González Escobedo, José Luis; Uusi-Kyyny, Petri; Puurunen, Riikka L.; Alopaeus, Ville. 2020. Hydrodeoxygenation Model Compounds γ-Heptalactone and γ-Nonalactone: Density from 293 to 473 K and H2 Solubility from 479 to 582 K. Journal of Chemical and Engineering Data, volume 65, issue 5, pages 2764–2773.
Full text in Acris/Aaltodoc: https://urn.fi/URN:NBN:fi:aalto-2020113020590
- [Publication 3]: Mäkelä, Eveliina; González Escobedo, José Luis; Lindblad, Marina; Käldström, Mats; Meriö-Talvio, Heidi; Jiang, Hua; Puurunen, Riikka L.; Karinen, Reetta. 2020. Hydrodeoxygenation of Levulinic Acid Dimers on a Zirconia-supported Ruthenium Catalyst. Catalysts, volume 10, issue 2, page 200.
Full text in Acris/Aaltodoc: https://urn.fi/URN:NBN:fi:aalto-202002282300
- [Publication 4]: Mäkelä, Eveliina*; González Escobedo, José Luis*; Neuvonen, Jouni; Lahtinen, Jouko; Lindblad, Marina; Lassi, Ulla; Karinen, Reetta; Puurunen, Riikka L. 2020. * These authors contributed equally. Liquid-phase Hydrodeoxygenation of 4-Propylphenol to Propylbenzene: Reducible Supports for Pt Catalysts. ChemCatChem, volume 12, issue 16, pages 4090–4104.
Full text in Acris/Aaltodoc: https://urn.fi/URN:NBN:fi:aalto-202008124675
- [Publication 5]: González Escobedo, José Luis; Mäkelä, Eveliina; Neuvonen, Jouni; Uusi-Kyyny, Petri; Lindblad, Marina; Karinen, Reetta; Puurunen, Riikka L. 2020. Hydrodeoxygenation of Propylphenols on a Niobia‐supported Platinum Catalyst: Ortho, Meta, Para Isomerism, Reaction Conditions, and Phase Equilibria. Advanced Sustainable Systems, volume 4, issue 10, page 1900140.
Full text in Acris/Aaltodoc: https://urn.fi/URN:NBN:fi:aalto-202101251569