Experimental study on blending diesel fuel with dimethyl carbonate with aid of ultrasonic emulsification process

Blending dimethyl carbonate (DMC, oxygenated fuel additive) with ultra low sulphur diesel fuel can lower soot emissions but the blend has poor stability and short shelflife. To address this problem, ultrasonic emulsification method was employed to improve the process. Multiple tests determined by orthogonal array approach were carried out to investigate impact of several factors (temperature, emulsifier content and processing duration) on blend stability. After blends were processed, their viscosities were measured and stabilities were quantified using the measurement of light absorbance (Abs) with an UV-visible spectrophotometer. The results suggested that this processing method can greatly enhance blend stability and slightly lower viscosity. The percentage of emulsifier was the most important factor, followed by temperature, while processing duration was the least deciding one. The optimised processing condition was obtained when ultrasonic exposure duration was 10 minutes, and temperature was 20°C with a gasoline content of 4% used as emulsifier.