Hydrodeoxygenation of lignin-derived phenolic compounds to hydrocarbons over Ni/SiO2–ZrO2 catalysts

Inexpensive non-sulfided Ni-based catalysts were evaluated for hydrodeoxygenation (HDO) using guaiacol as model compound. SiO2–ZrO2 (SZ), a complex oxide synthesized by precipitation method with different ratio of Si/Zr, was impregnated with Ni(NO3)2·6H2O and calcined at 500 °C. Conversion rates and product distribution for guaiacol HDO at 200–340 °C were determined. Guaiacol conversion reached the maximum at 300 °C in the presence of Ni/SZ-3. When HDO reaction was carried out with real lignin-derived phenolic compounds under the optimal conditions determined for guaiacol, the total yield of hydrocarbons was 62.81%. These hydrocarbons were comprised of cyclohexane, alkyl-substituted cyclohexane and alkyl-substituted benzene. They have high octane number, would be the most desirable components for fungible liquid transportation fuel.