Biobased chemicals from lignin

The prospects of declining crude oil reserves, a steady increase in energy demand, and concerns for the environment have intensified the search for renewable sources for energy generation, transportation fuels, and petrochemicals. Major breakthroughs have been made in the field of cellulose and hemi-cellulose conversions towards carbon based transport fuels (e.g. bioethanol and biodiesel) and biobased chemicals. However, valorization of lignin, the third major biopolymer in lignocellulosic biomass, is still in a state of infancy. Lignin, due to its aromatic nature, is expected to serve as an excellent starting material for the synthesis of aromatics and alkylated phenolics, which are important intermediates in the petrochemical industry. In this thesis, the use of a methodology known as catalytic hydrotreatment was used to convert lignin and particularly Alcell lignin to monomeric aromatics and alkylated phenolics. It involves contacting the lignin at elevated temperatures (400 °C) with hydrogen (100-200 bar), in the presence or absent of a solvent and a suitable, often heterogeneous catalyst. Attractive supported Ru-catalysts were identified for particularly the solvent free catalytic hydrotreatment version, product yields were determined and quantified using advanced GCxGC techniques and reaction pathways on a molecular level are proposed.