Abstract Furans (furfural and hydroxymethylfurfural) are the results of dehydration of monosaccharides, which can be obtained by acid hydrolysis of wood or other lignocellulosic materials. In this work, Pinus pinaster wood was subjected to aqueous autohydrolysis processing to obtain dissolved hemicellulose-derived polymeric or oligomeric saccharides made up of mannosyl, glucosyl, galactosyl, xylosyl, and arabinosyl structural units. The aqueous liquors were then heated in the presence of sulfuric acid and methyl isobutyl ketone to obtain furans. The effects of selected operational variables, such as the ratio of organic to aqueous phase, temperature, and reaction time, were assessed by empirical modeling in terms of the conversion into furans and levulinic acid. The maximum furfural conversion (71.4%) was predicted to occur operating at 165°C and a ratio of organic to aqueous phase of 2 for 68.5 min. In additional experiments, dimethyl sulfoxide and/or 1-butanol were added to the aqueous phase and the change in furan conversion rates was observed.