Overview of the recent advances in lignocellulose liquefaction for producing biofuels, bio-based materials and chemicals

The concerns over the increasing energy demand and cost as well as environmental problems derived from fossil fuel use are the main driving forces of research into renewable energy. Lignocellulosic biomass comprised of cellulose, hemicellulose, and lignin is an abundant, carbon neutral, and alternative resource for replacing fossil fuels in the future. Solvent liquefaction of lignocellulosic biomass is a promising route to obtain biofuels, bio-based materials, and chemicals using a range of solvents as reaction media under moderate reaction conditions. Recently, several researchers have considered novel approaches for enhancing the process efficiency and economics. This review article reports the state-of-the-art knowledge of lignocellulose liquefaction in the recent three years with the main focus on the feedstock, liquefaction technology, target products, and degradation mechanism of each biomass component. This review is expected to provide an important reference for research into the solvent liquefaction of lignocellulose in the near future.