Kinetic Studies of Lignin Solvolysis and Reduction by Reductive Catalytic Fractionation Decoupled in Flow-Through Reactors
© 2018 American Chemical Society. Reductive catalytic fractionation (RCF) is an effective active-stabilization strategy to selectively extract and depolymerize lignin into aromatic monomers. Here, the kinetics of RCF were investigated by using flow-through reactors to decouple the two limiting mecha...
| Main Authors: | , , , , |
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| Format: | Article |
| Language: | English |
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American Chemical Society (ACS)
2021
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| Online Access: | https://hdl.handle.net/1721.1/134625 |
| _version_ | 1826212990157848576 |
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| author | Anderson, Eric M Stone, Michael L Hülsey, Max J Beckham, Gregg T Román-Leshkov, Yuriy |
| author2 | Massachusetts Institute of Technology. Department of Chemical Engineering |
| author_facet | Massachusetts Institute of Technology. Department of Chemical Engineering Anderson, Eric M Stone, Michael L Hülsey, Max J Beckham, Gregg T Román-Leshkov, Yuriy |
| author_sort | Anderson, Eric M |
| collection | MIT |
| description | © 2018 American Chemical Society. Reductive catalytic fractionation (RCF) is an effective active-stabilization strategy to selectively extract and depolymerize lignin into aromatic monomers. Here, the kinetics of RCF were investigated by using flow-through reactors to decouple the two limiting mechanistic steps, namely lignin solvolysis and reduction. When operating in a solvolysis-limited regime, apparent energy barriers of 63 ± 1 and 64 ± 2 kJ mol-1 were measured for the solvent mediated lignin extraction of poplar using particle diameters of 0.5 < d < 1 mm and 0.075 < d < 0.25 mm, respectively. In contrast, when using mechanically stirred batch reactors, apparent barriers of 32 ± 1 and 39 ± 3 kJ mol-1 were measured for particle diameters of 0.5 < d < 1 mm and 0.075 < d < 0.25 mm, respectively. The difference of activation barriers between flow and batch reactors indicated that lignin extraction under typical RCF conditions in a 100 mL batch reactor stirred at 700 rpm was mass-transfer limited. In the reduction-limited regime, cleavage of the β-O-4 bond in a model compound exhibited an apparent activation barrier of 168 ± 14 kJ mol-1. This study demonstrates RCF occurs by two limiting processes that can be independently controlled. Furthermore, both controlling which process limits RCF and verifying if transport limitations exist, are critical steps to develop a mechanistic understanding of RCF and to design improved catalysts. |
| first_indexed | 2024-09-23T15:41:20Z |
| format | Article |
| id | mit-1721.1/134625 |
| institution | Massachusetts Institute of Technology |
| language | English |
| last_indexed | 2024-09-23T15:41:20Z |
| publishDate | 2021 |
| publisher | American Chemical Society (ACS) |
| record_format | dspace |
| spelling | mit-1721.1/1346252023-01-20T20:46:01Z Kinetic Studies of Lignin Solvolysis and Reduction by Reductive Catalytic Fractionation Decoupled in Flow-Through Reactors Anderson, Eric M Stone, Michael L Hülsey, Max J Beckham, Gregg T Román-Leshkov, Yuriy Massachusetts Institute of Technology. Department of Chemical Engineering © 2018 American Chemical Society. Reductive catalytic fractionation (RCF) is an effective active-stabilization strategy to selectively extract and depolymerize lignin into aromatic monomers. Here, the kinetics of RCF were investigated by using flow-through reactors to decouple the two limiting mechanistic steps, namely lignin solvolysis and reduction. When operating in a solvolysis-limited regime, apparent energy barriers of 63 ± 1 and 64 ± 2 kJ mol-1 were measured for the solvent mediated lignin extraction of poplar using particle diameters of 0.5 < d < 1 mm and 0.075 < d < 0.25 mm, respectively. In contrast, when using mechanically stirred batch reactors, apparent barriers of 32 ± 1 and 39 ± 3 kJ mol-1 were measured for particle diameters of 0.5 < d < 1 mm and 0.075 < d < 0.25 mm, respectively. The difference of activation barriers between flow and batch reactors indicated that lignin extraction under typical RCF conditions in a 100 mL batch reactor stirred at 700 rpm was mass-transfer limited. In the reduction-limited regime, cleavage of the β-O-4 bond in a model compound exhibited an apparent activation barrier of 168 ± 14 kJ mol-1. This study demonstrates RCF occurs by two limiting processes that can be independently controlled. Furthermore, both controlling which process limits RCF and verifying if transport limitations exist, are critical steps to develop a mechanistic understanding of RCF and to design improved catalysts. 2021-10-27T20:05:51Z 2021-10-27T20:05:51Z 2018 2019-09-10T18:41:36Z Article http://purl.org/eprint/type/JournalArticle https://hdl.handle.net/1721.1/134625 en 10.1021/ACSSUSCHEMENG.8B01256 ACS Sustainable Chemistry & Engineering Article is made available in accordance with the publisher's policy and may be subject to US copyright law. Please refer to the publisher's site for terms of use. application/pdf American Chemical Society (ACS) ACS |
| spellingShingle | Anderson, Eric M Stone, Michael L Hülsey, Max J Beckham, Gregg T Román-Leshkov, Yuriy Kinetic Studies of Lignin Solvolysis and Reduction by Reductive Catalytic Fractionation Decoupled in Flow-Through Reactors |
| title | Kinetic Studies of Lignin Solvolysis and Reduction by Reductive Catalytic Fractionation Decoupled in Flow-Through Reactors |
| title_full | Kinetic Studies of Lignin Solvolysis and Reduction by Reductive Catalytic Fractionation Decoupled in Flow-Through Reactors |
| title_fullStr | Kinetic Studies of Lignin Solvolysis and Reduction by Reductive Catalytic Fractionation Decoupled in Flow-Through Reactors |
| title_full_unstemmed | Kinetic Studies of Lignin Solvolysis and Reduction by Reductive Catalytic Fractionation Decoupled in Flow-Through Reactors |
| title_short | Kinetic Studies of Lignin Solvolysis and Reduction by Reductive Catalytic Fractionation Decoupled in Flow-Through Reactors |
| title_sort | kinetic studies of lignin solvolysis and reduction by reductive catalytic fractionation decoupled in flow through reactors |
| url | https://hdl.handle.net/1721.1/134625 |
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