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Due to the increasing crude oil price and the environmental concerns about air pollution and greenhouse gas emission, studies about substitute for diesel fuels are important and necessary for a sustainable world.Biodiesel has attracted attention during the past decades as a renewable and environmental friendly fuel.Transesterification catalyzed by solid base catalysts in biodiesel production seems more preferable in consideration of their high catalytic activity and low cost.Although the study on biodiesel production using solid base catalysts was already reported in several research papers, deeper study of heterogeneous catalysis biodiesel forming reactions should be carried out for more understanding of the reaction kinetics and mechanism.In this paper, K2CO3/Ca-Al hydrotalcite was used as a heterogeneous catalyst and its catalytic activity was investigated in a well-mixed batch reactor, with a methanol to palm oil molar ratio 12 to 1 and 5 % (wt/wt oil)catalyst amount as constant parameters.The second ordered reversible reaction was established and FAME yields were followed as a function of temperature (318-338 K) and reaction time (1-7 h).Method of multiple non-linear regressions was used to estimate the two model parameters (k1 and k2).The activation energy (Ea) of forward and reverse reaction calculated from Arrhenius equation was 136.21 kJ/mol and 58.84 kJ/mol respectively.Comparison between the oil conversion calculated by the kinetic equation and experiment result showed that the model calculation data almost agreed with the experiment data, which meant the pseudo-homogeneous second order mechanism model was appropriate to describe the kinetics of transesterification between palm oil and methanol catalyzed by K2CO3/Ca-Al hydrotalcite solid base.