Conversion of cellulose to furans catalyzed by zinc chloride under microwave irradiation

Cellulose was degraded in concentrated ZnCl₂ solution which acted as a solvent and catalyst under microwave irradiation. Cellulose was directly converted into two main furans, 5-hydroxymethyl furfural (5-HMF) and 1-(furan-2-yl)-2-hydroxyethanone. Factors affecting the mol yields of these two compounds were investigated at different temperatures, reaction times, concentrations of ZnCl₂, cellulose contents, and microwave powers. For 1 g cellulose reacted with 140 mL 69% ZnCl₂ solution, the mol yields of 5-HMF reached to 19.4% under the microwave power of 500 W and 1-(furan-2-yl)-2-hydroxyethanone reached to 12.0% under the microwave power of 600 W at 135 ℃ within 5 min.