Solid base catalysts used in the transesterification for biodiesel production can simplify the technological processes

especially the separation process of productsBy screening metal oxides

calcium oxide was found to be a potential catalyst for the transesterification of rapeseed oilImpregnating calcium acetate solution onto MgO carrier and calcining the impregnated sample obtained a CaO/MgO catalyst containing 165%(mass) of calcium oxide

which exhibited a high activity in the transesterification reactionBy using this catalyst

under the condition of 64.5℃

a methanol/oil molar ratio of 18∶1 and a catalyst dosage of 2%

oil conversion reached 92% in 3.5 h

which was close to the oil conversion using the traditional NaOHFurthermore

the solid catalysts obtained were characterized with XRD

AAS

XPS and CO2-TPDThe results showed that the basicity of the catalysts greatly affected their activitiesProperly selecting the carrier

precursor and Caloading could increase the strong basic sites

and therefore increase their catalytic activity.