Kinetic study of glycerol hydrodeoxygenation on Al2O3 and NiMo2C/Al2O3 catalysts

Abstract

A kinetic study of glycerol hydrodeoxygenation (HDO) on NiMo2C/Al2O3 and Al2O3, prepared by sol-gel technique, was carried out in a batch reactor, from 250 °C to 285 °C, at high glycerol concentration (95wt%). Structural and surface properties of the catalysts were determined by XRD, nitrogen physisorption, TEM and NH3-TPD. Impregnation of alumina with Ni and Mo and subsequent carburization at 730 °C increased crystallite sizes and reduced total acidity of the catalyst to 1/3 that of pure alumina. All reactions were well fitted to a zeroth order model. Estimation of reagents mass transport rates suggests no diffusion limitation. Main products were propanediols, ethylene glycol and long-chain molecules from oligomerization reactions, as well as methane, ethane and propane. At this temperature range, long-chain compounds have the highest yields, mainly on alumina.