Fast pyrolysis of rice husk under vacuum conditions to produce levoglucosan

Levoglucosan (LG)-enriched pyrolytic oils were obtained from rice husk by lab-scale fast pyrolysis under vacuum conditions. We studied the effect of temperature (300−700 °C) and pretreatment biomass, on product yields selectivity for LG formation. The maximum oil yield (47 wt.%) was hydrochloric acid-leached at 400 °C, producing 1.4 times more than amount produced untreated same temperature. Anhydrosugars predominant compounds found in bio-oils all conditions assessed, being main product. Depending conditions, concentration between 9−30 wt.% considering bio-oil mass, 4−60 initial cellulose mass. 1H NMR experiments carried out as an alternative simple technique to directly determine bio-oils.