It is hoped to develop a simple and low cost route for preparing the CaO with a novel morphology which can present high catalytic activity in catalyzing transesterification reaction for biodiesel. The porous CaO microsphere was synthesized by calcining spherical CaCO3 precursor which was prepared easily by mixing CaCl2 with Na2CO3. The as-prepared CaO microsphere was characterized by scanning electronic microscopy(SEM), powder X-ray diffractometry(XRD) and N2 adsorption experiment. The results reveal that the synthesized CaO is regular microsphere with many pores in its exterior and interior. The CaO microsphere is applied in catalyzing the transesterification reaction of soybean oil for biodiesel and presents excellent catalytic ability with a transesterification yield of 98.72%. This catalyst could have potential applications in other fields in view of its well-defined morphology, simply synthetic route and low cost.
