Emulsion Fuels Production between Diesel and Bio-Oil Middle Fraction from Molecular Distillation
In this paper, emulsification study on bio-oil middle fraction and diesel was carried out. Mechanical and ultrasound emulsification technologies were used to prepare emulsion fuels between bio-oil middle fraction and diesel with different hydrophile and lipophile balance (HLB) values. It was found that the stability curve of emulsions had two peaks corresponding to the HLB values of 4.3 and 6, respectively. Comparable to the mechanical emulsions, the ultrasound emulsions had longer stable time. The stable time for ultrasound emulsions at the HLB values of 4.3 and 6 were 215 minutes and 143 minutes, respectively. Then the effects of surface tension and droplet size distribution on the stability of emulsions were investigated. It was found that the emulsion fuels with lower surface tension and smaller droplet size had longer stable time.