Thermodynamic equilibrium analysis of the vapor phase hydrodeoxygenation of guaiacol

Vapor phase hydrodeoxygenation (HDO) is a prospective route for upgrading the downstream products derived from fast pyrolysis of lignocellulosic biomass. The objective is to produce transportation fuel or value-added chemicals using a sustainable feedstock. This work reports a thermodynamic chemical equilibrium analysis of the vapor phase HDO of guaiacol (2-methoxyphenol), model compound representative of the lignin portion of biomass,. The chemical equilibrium was determined by simulation in the temperature range of 500–1000 K, 1 atm, and using an isothermal equilibrium reactor. These conditions were chosen to match the atmospheric HDO of guaiacol studies. The equilibrium constant and the equilibrium conversion values determined may help on the explanation of reaction pathways of the catalytic HDO of guaiacol. Most of the reactions behaved exothermically and did not show thermodynamic restriction to occur, except the hydrogenation of the aromatic ring. The desirable reactions which remove oxygen without breaking C–C bonds were thermodynamically favored. The most stable molecules were dependent on both temperature and guaiacol concentration at feed. [Display omitted] •Gas-phase guaiacol hydrodeoxygenation thermodynamics analysis.•Thermodynamics models by Gibbs and equilibrium reactors.•Direct deoxygenation (DDO) reactions are favored thermodynamically.