Investigation of solvent effects on the hydrodeoxygenation of guaiacol over Ru catalysts

Roldán

Kishore

et al. 2022

Catal. Sci. Technol.

“…Open towards dehydroxygenation of phenol rather than hydrogenation is in strong agreement with observations involving noble metal catalysts 28,53,70 , and in non-catalytic works 71 .…”

Section: Catalysis Science and Technology Accepted Manuscriptsupporting

confidence: 88%

Hydrodeoxygenation of guaiacol over orthorhombic molybdenum carbide: a DFT and microkinetic study

Roldán

Kishore

et al. 2022

Catal. Sci. Technol.

“…Therefore, the reaction will proceed via R33 to form structure 25, which will then be hydrogenated to form structure 29, benzene. The preference in our calculations towards dehydroxygenation of phenol rather than hydrogenation is in strong agreement with observations involving noble metal catalysts 26,49,64 , and in non-catalytic works 65 .…”

Section: Energy Profile Of the Upgrading Routessupporting

confidence: 91%

Hydrodeoxygenation of Guaiacol Over Orthorhombic Molybdenum Carbide: A DFT and Microkinetic Study

Roldan²,

Kishore³

et al. 2021

Preprint

The hydrodeoxygenation of guaiacol is modelled over a (100) β-Mo2C surface using density functional theory and microkinetic simulations. The thermochemistry of the process shows that the demethoxylation of the guaiacol, to form phenol, will be the initial steps, with a reaction energy of 29 kJ/mol (i.e. endothermic) and a highest activation barrier of 112 kJ/mol. Subsequently, the dehydroxylation of the phenol, which has a rate-determining activation barrier of 145 kJ/mol, will lead to the formation of benzene, with an overall reaction energy for conversion from guaiacol of -91 kJ/mol (i.e. exothermic). The sp2 and sp hybridized carbon atoms of the molecular functional groups are found to dissociate on the surface with minimum energy barriers, while the hydrogenation of the adsorbed molecules requires higher energy. The microkinetic modelling, which is performed considering typical reaction conditions of 500 to 700 K, and a partial pressure ratio H2:guaiacol of 1, shows quick formation and accumulation of phenol on the surface with increasing temperature, although high temperatures mitigate the guaiacol adsorption step. Based on simulated temperature programmed desorption (TPD), maximum conversion of guaiacol can be expected at 70% surface coverage of this species.

Section: Energy Profile Of the Upgrading Routessupporting

confidence: 91%

Hydrodeoxygenation of Guaiacol Over Orthorhombic Molybdenum Carbide: A DFT and Microkinetic Study

Roldán

Kishore

et al. 2021

Preprint

The hydrodeoxygenation of guaiacol is modelled over a (100) β-Mo2C surface using density functional theory and microkinetic simulations. The thermochemistry of the process shows that the demethoxylation of the guaiacol, to form phenol, will be the initial steps, with a reaction energy of 29 kJ/mol (i.e. endothermic) and a highest activation barrier of 112 kJ/mol. Subsequently, the dehydroxylation of the phenol, which has a rate-determining activation barrier of 145 kJ/mol, will lead to the formation of benzene, with an overall reaction energy for conversion from guaiacol of -91 kJ/mol (i.e. exothermic). The sp 2 and sp hybridized carbon atoms of the molecular functional groups are found to dissociate on the surface with minimum energy barriers, while the hydrogenation of the adsorbed molecules requires higher energy.The microkinetic modelling, which is performed considering typical reaction conditions of 500 to 700 K, and a partial pressure ratio H2:guaiacol of 1, shows quick formation and accumulation of phenol on the surface with increasing temperature, although high temperatures mitigate the guaiacol adsorption step. Based on simulated temperature programmed desorption (TPD), maximum conversion of guaiacol can be expected at 70% surface coverage of this species.