title: A revisited picture of the mechanism of glycerol dehydration.
abstract: The dehydration mechanism of neutral glycerol in the gas phase was investigated by means of metadynamics simulations. Structures, vibrational frequencies, Gibbs free energy barriers, and rate constants at 800 K were computed for the different steps involved in the pyrolytic process. In this article, we provide a novel mechanism for the dehydration of neutral glycerol, proceeding via formation of glycidol with a barrier of 66.8 kcal/mol. The formation of glycidol is the rate limiting step of the overall decomposition process. Once formed, glycidol converts into 3-hydroxypropanal with a barrier of 49.5 kcal/mol. 3-Hydroxypropanal can decompose further into acrolein or into formaldehyde and vinyl-alcohol with barriers of 53.9 and 35.3 kcal/mol, respectively. These findings offer new insights to available experimental data based on glycerol pyrolysis studies performed with isotopic labeling and on the interpretation of the chemistry of glycerol and sugars in pyrolytic conditions.
authors: IBM Research-Zurich, Rüschlikon, Switzerland. teo@zurich.ibm.com
authors: Teodoro
authors: T
authors: Laino
authors: Christian
authors: C
authors: Tuma
authors: Alessandro
authors: A
authors: Curioni
authors: Evan
authors: E
authors: Jochnowitz
authors: Steffen
authors: S
authors: Stolz
mesh_terms: D003681:Dehydration; D005990:Glycerol / Q000737:chemistry*; D011789:Quantum Theory; D013816:Thermodynamics
chemical_list: D005990:Glycerol