Enhancing waste eggshell-derived CaO catalysts for biodiesel production through synergistic oxide modification: a comprehensive catalytic and kinetic study

giving the highest operational TOF, indicating improved site accessibility rather than intrinsically faster kinetics. The modified catalysts demonstrated minimal deactivation (<2% loss over four cycles), attributed to oxide-induced stabilization of CaO active sites. This work provides new mechanistic insight into cooperative adsorption and site utilization in waste-derived CaO catalysts, advancing the rational design of durable heterogeneous catalysts for biodiesel synthesis.