Vanillyl alcohol was chosen as a model component for lignin-derived components in bio-oil. The catalytic conversion of vanillyl alcohol over different catalysts was studied and it has been shown that this model component has undergone consecutive reactions to form methoxy phenols, phenols, and eventually hydrocarbons with increasing degree of de-oxygenation. The degree of de-oxygenation of vanillyl alcohol was shown to increase with the increase in number of acid sites in catalysts. γ-Al2O3 material with the highest number of acid sites has resulted in the highest yield of aromatic hydrocarbons, accompanied by the highest yields of coke and gas compared to other materials used in this study. Two pathways have been shown leading to the formation of hydrocarbons from vanillyl alcohol, which are: (i) decomposition of vanillyl alcohol into small olefinic hydrocarbon fragments and the subsequent aromatisation into final products and (ii) direct de-oxygenation of this model component over catalysts.
- Model compound