Abstract- Calcined eggshell was investigated in rapeseed oil transesterification with a view to determine its viability as a
solid catalyst for use in biodiesel synthesis. Response Surface Methodology (RSM) was used to optimize the biodiesel
production parameters. A quadratic polynomial equation was obtained for biodiesel yield by multiple regression analysis.
Interactions between the variables were validated statistically. The optimum conditions of the independent variables in the
present work were 9:1 molar ratio of methanol to oil, 3 wt% calcined eggshell catalyst (calcined at 900˚C, 2 hr), 60˚C
reaction temperatures at reaction time of 3 h. The predicted biodiesel yield was 96 % under the optimal conditions.
Reusability and effect of calcination temperature on activity of eggshell catalysts were also investigated. The catalyst was
characterized by X-ray diffraction (XRD), N2 adsorption-desorption and Fourier transform infrared spectrometry (FTIR).