An investigation on the catalytic capability of the modified white mud after activation in transesterification and kinetic calculation

• MWM activated at a lower temperature gains a more developed microstructure.
• The capability of MWM in catalyzing transesterification is strengthened.
• The MWM catalyzed transesterification supplies an efficiency of 97.43%.
• The properties of the produced biodiesel are in accordance with ASTM D 6751.
• MWM catalyzes transesterification with the activation energy of 66.82 kJ mol−1.

White mud is modified by acetic acid and then activated at 700 °C to catalyze transesterification. After modification and activation, the prepared catalyst (labeled as MWM–700) mainly consists of calcium oxide with a surface area of 7.97 m2 g−1 and basic strength of 9.8 < H_ < 15.0. Under the optimized condition of the catalyst added amount of 6 wt%, molar ratio of methanol to oil of 15, reaction temperature of 64 °C and reaction time of 150 min, the MWM–700 catalyzed transesterification of peanut oil with methanol supplies an efficiency of 97.43%. With the seventh time usage, a catalytic efficiency of 89.33% is still supplied. Meanwhile, the repeated experiments are conducted to confirm the reproducibility and reliability of the experimental results. The chemical structure and physical properties of the produced biodiesel are detected, which are in accordance with ASTM D 6751. Finally, the kinetic parameters of the MWM–700 catalyzed transesterification are calculated, where the activation energy is 66.82 kJ mol−1 and the pre-exponential factor is 1.36 × 109 min−1.