The heterogeneously catalyzed synthesis of biodiesel via the transesterification reaction of canola oil was investigated. The oil was converted into fatty acid methyl ester (FAME) under the catalytic activity of CaO nanoparticles, which were impregnated with 3-10% of K2CO3. The functionalized CaO enabled the methyl ester yield to reach 97.67% +/- 1.7 in 8 h of reaction time in a liquid batch reactor at 338 K and using an alcohol/ oil ratio of 9/1. The apparent reaction order and the activation energy of the transesterification reaction of triglycerides were determined as 0.98 and 25.34 +/- 2.48 kJ/ mol, respectively. The kinetic data indicated that the transesterification reaction was mass transfer, i.e., diffusion controlled, pointing to how the reaction rate can be increased. (C) 2015 Elsevier Ltd. All rights reserved.