Influence of acetone addition on the physicochemical properties of bio-oils

In order to improve the physicochemical properties of bio-oil, acetone at different mass concentrations (3 wt.%, 6 wt.%, 9 wt.%, 12 wt.% and 15 wt.%, respectively) was added into the bio-oil. The physicochemical properties of blank (untreated bio-oil) and blended bio-oil were investigated every 7 days for a storage period of 35 days. The results indicate that acetone had a significant effect on improving the physicochemical properties of bio-oil. In addition, it is shown that with acetone concentration increased, the final pH values were increased by 1.71, 3.43, 4.00, 6.29 and 8.00%, respectively. The final water contents were decreased by 5.45, 8.09, 9.44, 12.13 and 12.01%, respectively. The final viscosities were decreased by 37.20, 57.78, 71.92, 79.79 and 84.67%, respectively. FTIR and GC–MS data indicate that acetone likely inhibited some ageing reactions of bio-oil and acetone itself joined the ageing reactions which bring some new substances. But there was no obvious evidence showing the relationship between the effects and mass concentration of acetone.