Determination and comparison of the activation energies of biodiesel microemulsion and biodiesel blends

Ignition delay is commonly used to evaluate biodiesel ignition quality and it is positively correlated to the activation energy of biodiesel. This study compared the effect of microemulsification and biodiesel/diesel blending on activation energies using thermogravimetric analysis. Water-in-biodiesel microemulsion was formed by the assistant of surfactant rhamnolipid (RL), with activation energies of water-in-biodiesel microemulsion and biodiesel/diesel blends being calculated for assessing thermal oxidation and ignition properties of these biodiesel hybrid fuels. T-max values (the temperature at maximum decomposition rate) of biodiesel hybrid fuels were shifted to higher temperatures and DTG(max) (the maximum decomposition rate) decreased upon the formation of microemulsion. Biodiesel microemulsification had the same effect on reduction of activation energy of biodiesel as blending diesel into biodiesel (50/50, V/V). The activation energy at lower conversion rate (alpha) was reduced significantly, demonstrating the great potential of using microemulsification to improve the ignition properties of the biodiesel.

Automated summary

This study compared the effect of microemulsification and biodiesel/diesel blending on activation energies and found that both methods had similar effects on reducing the activation energy of biodiesel, indicating the potential for improving the ignition properties of biodiesel.