摘要
Growing interest is being paid to the development of environmentally friendly technologies for producing fuels and chemicals from renewable resources. In this scope, Pinus pinaster wood samples were treated with water under optimized conditions to solubilize the hemicellulose fraction, leaving a solid phase containing cellulose and lignin (which could be used for specific purposes according to a biorefinery approach). The major reaction products were soluble oligo- or poly-saccharides made up of mannose, glucose, galactose, xylose and arabinose. Hemicellulosic saccharides were processed in media containing the ionic liquid 1-butyl-3-methylimidazolium chloride using chromium (III) chloride as a catalyst to produce furans (hydroxymethylfurfural from hexoses and furfural from pentoses) operating at a fixed substrate loading (10 wt%). The kinetic pattern corresponded to a complex reaction scheme involving the saccharification of the polymeric and oligomeric species into the various constituent units, and the further dehydration of these latter into furans. The effects of temperature and reaction time on the product distribution were assessed in selected experiments. Operating at 10% substrate loading, up to 12.1 g HMF/L were obtained. Furfural production from HS proceeded with a faster kinetics, and was obtained at 37.7% conversion. The experimental data confirmed the potential of the environmentally friendly method proposed in this work to produce furans from pine hemicelluloses, as well as for enabling an integral benefit of the feedstock according to the biorefinery philosophy.