Production of 5-Hydroxymethylfurfural from pine wood via biorefinery technologies based on fractionation and reaction in ionic liquids

Abstract

Pine wood is mainly composed of extractives, lignin, cellulose, and hemicelluloses (which include pentosans and hexosans). In the scope of biorefineries, the utilization of pine wood entails the selective separation of its major components. A sequence of aqueous and delignification treatments enables the selective separation of hemicelluloses (as soluble products from the aqueous fractionation step), lignin (as soluble products from the delignification stage), and cellulose (accumulated in the solid phase leaving the delignification stage). Delignification was done in media containing acetic acid or the ionic liquid 1-butyl-3-methylimidazolium hydrogen sulfate. Both the soluble hemicellulose-derived saccharides and the cellulose-containing solids were found to be suitable substrates for 5-hydroxymethylfurfural production in reaction media containing the ionic liquid 1-butyl-3-methylimidazolium chloride in the presence of Brønsted and/or Lewis acidic catalysts. The processing schemes considered in this work allowed an efficient utilization of the feedstock using environmentally friendly technologies.