Upgrading of Bio-oil via Esterification Catalysted with Acidic Ion-exchange Resin

The corrosiveness of bio-oils is derived from organic acids, and it has limited the applications of bio-oil for current vehicles. But these acids can react with alcohol and convert into esters under mild condition with proper catalysts. The super-acid ion-exchange resin was applied to upgrade bio-oil and its light distillation fraction. The esterifiaction of bio-oils were preformed at 60 degrees C for 4 It, and the conversion of acetic acid approached 88%. Furthermore, the properties of bio-oils after esterification were improved significantly: the higher heating value approached 20.08 and 18.33 MJ/kg, which improved 19.5% and 43.6%,respectively. The viscosity was decreased from 11.8 and 1.42 mm(2)/s to 3.77 and 1.12 mm(2)/s, respectively; and the moisture is about 23.7% and 28.4% (mass fraction). The results of GC-MS show that organic acids in both bio-oils were successfully transformed into esters, primary ethyl acetate. Furthermore, the ion-exchanged resin could be convenient separated and reused, and would be a promising catalyst for upgrading of bio-oil.