Butyl-biodiesel production from waste cooking oil: Kinetics, fuel properties and emission performance

Abstract

Butyl-biodiesel is produced by the transesterification of waste cooking oil and n-butanol. The sulfamic acid, a kind of heterogeneous acid, is used as the substitute of sulfuric acid to catalyze the reaction. The yield of biodiesel can reach 95.6% at the optimal reaction conditions (molar ratio of n-butanol to oil is 10:1, catalyst amount is 1.0 wt% (based on oil), reaction temperature is 110 °C and reaction time is 2 h). Besides, a pseudo second-order reaction kinetics is also established at the temperature range of 90–110 °C and the activation energy of 80.3 kJ/mol is calculated by the Arrhenius equation. Moreover, when compared with the FAMEs, the cold flow performance of FABEs is improved and the cold filter plugging point (CFPP) of FABEs is significantly decreased from 6.5 °C to 2 °C. Finally, the bench test was also investigated to make a detail comparison of the engine performance and the CH, CO, NOx and PM emissions of FAMEs, FABEs and 0# diesel.