Bio based fuels and fuel additives from lignocellulose feedstock via the production of levulinic acid and furfural

Abstract
The demand for biomass-derived fuels and fuel additives, particularly in the transportation sector, has stimulated intense research efforts in the chemistry of levulinic acid and levulinic acid secondary products over the past decade. Additionally, recent technological progress in lignocellulosic feedstock (LCF) chemistry has also increased attention in this regard. As a result, several oxygenating fuel additives with potential applications in both gasoline and diesel fuels have been identified. Some of the chemicals, such as ethyl valerate, appear to be viable alternatives to the currently used branched, short-chain ethers that are derived from side products of petrol refining. Cost-effective applications of lignocellulosic biomass are a crucial aspect of its feasibility. In consideration of the LCF biorefinery concept, the feasibility must also include the chemical pulping of LCF and the comprehensive utilisation of its main constituents cellulose, hemicelluloses, and lignin. The present study focuses on cellulose and hemicelluloses as viable sources for the production of biofuels and biofuel additives. Multifunctional catalysis, including hydrogenation and acid catalysis are the primary instruments used for the conversion of the monomeric carbohydrate building blocks, i.e., mainly C5 sugars, such as xylose and arabinose, and C6 sugars in the form of glucose and their respective secondary products, furfural and levulinic acid. Lignin utilisation is not addressed in this paper.