Abstract |
The thermochemistry of the conversion of glucose to levulinic acid through fructofuranosyl intermediates is investigated using the high-level ab initio methods G4 and G4MP2. The calculated gas phase reaction enthalpies indicate that the first two steps involving water molecule elimination are highly endothermic, while the other steps, including additional water elimination and rehydration to form levulinic acid, are exothermic. The calculated gas phase free energies indicate that inclusion of entropic effects makes the dehydration steps more favorable, although the elimination of the first water is still endothermic. Elevated temperatures and aqueous reaction environments are also predicted to make the dehydration reaction steps thermodynamically more favorable. On the basis of these enthalpy and free energy calculations, the first dehydration step in conversion of glucose to levulinic acid is likely a key step in controlling the overall progress of the reaction. An assessment of density functional theories and other theoretical methods for the calculation of the dehydration and hydration reactions in the decomposition of glucose is also presented.
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Authors | Rajeev S Assary, Paul C Redfern, Jeff R Hammond, Jeffrey Greeley, Larry A Curtiss |
Journal | The journal of physical chemistry. B
(J Phys Chem B)
Vol. 114
Issue 27
Pg. 9002-9
(Jul 15 2010)
ISSN: 1520-5207 [Electronic] United States |
PMID | 20572641
(Publication Type: Journal Article, Research Support, U.S. Gov't, Non-P.H.S.)
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Chemical References |
- Formates
- Levulinic Acids
- Solvents
- formic acid
- 5-hydroxymethylfurfural
- Furaldehyde
- Glucose
- levulinic acid
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Topics |
- Formates
(chemistry)
- Furaldehyde
(analogs & derivatives, chemistry)
- Glucose
(chemistry)
- Levulinic Acids
(chemistry)
- Models, Molecular
- Molecular Conformation
- Quantum Theory
- Solvents
(chemistry)
- Thermodynamics
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