In the present study, CaO-SiO2 catalysts were successfully synthesized through a biomimetic silicification approach by using eggshell and Na2SiO3 as raw materials. More specifically, the powdered egg shells, where lysozyme (the inducer) was located, were dispersed into Na2SiO3 aqueous solution to implement the biomimetic silicification under ambient conditions. The as-obtained egg shell-SiO2 composites were then calcined at 800 degrees C under oxygen atmosphere, thus acquiring the CaO-SiO2 catalysts. These catalysts were detailedly characterized by SEM, EDS, Si-29 NMR, FTIR, XRD, BET analysis, and Hammett indicator. When utilized for catalytic transesterification of palm oil, the CaO-SiO2 catalysts exhibited decreased catalytic activity and increased reusability as the amount of Si compounds increased. Particularly, when the Na2SiO3 concentration was below 0.4 M, a slight decrease in the catalytic activity could be observed (0Si5Ca, 1Si5Ca and 2Si5Ca showed good performance with biodiesel yields of 90.2%, 87.7% and 80.1%, respectively), whereas the reusability of the catalyst was significantly improved (little deactivation was found after 12 cycles on the 2Si5Ca catalyst during the transesterification reaction). Hopefully, this biomimetic silicification approach can be applied for the synthesis of a wide range of efficient and stable solid base catalysts for transesterification/esterification reactions. (C) 2015 Elsevier Ltd. All rights reserved.