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Dimethyl carbonate (DMC) is well known as an extremely industrially valuable substance. The demand for high-efficiency synthesis of DMC has greatly driven the exploration of novel catalysts and their low-cost preparation methods. Herein, a novel method for the rapid batch preparation of CaO/carbon catalysts using calcium citrate (CaCi) was provided, and these catalysts were used to catalyze the transesterification reaction of methanol and ethylene carbonate (EC) to synthesize DMC and ethylene glycol (EG). Accordingly, the structure and properties of the catalysts were characterized using XRD, FTIR, N2 adsorption–desorption, TG, TG-IR, CO2-TPD, XPS, SEM, TEM and ICP-OES techniques. Meanwhile, the effect of various process conditions such as carbonization temperature, reaction temperature, reaction time and catalyst amount has been extensively evaluated. Under the optimal process parameters, the conversion of EC and the selectivity of DMC and EG were 81.2, 99.3 and 99.5%, while the turnover number (TON) and turnover frequency (TOF) were 54.1 and 162 h−1, respectively. Furthermore, kinetic analysis was carried out, and the value of k (reaction rate constant) was ≈0.159 mol L−1 min−1. The reusability was also investigated. [ABSTRACT FROM AUTHOR]

Dimethyl carbonate (DMC) is an important environmentally‐friendly organic compound. The need for efficient synthesis of DMC has given a fillip to search for new catalysts and their cost‐effective preparation. In this work, a series of KAlO2/γ‐Al2O3 heterogeneous catalysts were rapidly prepared by impregnation method. These catalysts were characterized by FTIR, XRD, XPS, TG‐MS, ICP‐OES, BET and Hammett acid‐base titration and tested for the synthesis of DMC via transesterification from ethylene carbonate (EC) with methanol. The results demonstrated that KAlO2, as the active species, was produced in large quantities during the calcination process. The catalyst with a calcination temperature of 700 °C and a K2CO3 loading of 45 wt % exhibited the best catalytic activity. The optimum conditions for the process resulted in a catalyst amount of 1.0 wt %, a reaction temperature of 100 °C and a reaction time of 80 min, in which the EC conversion and DMC selectivity were 80.2 % and 98.9 %, respectively. In addition, the TON, TOF and reaction rate were 80.3, 61.2 h−1 and 3.91 gDMC⋅gcat−1⋅min−1. The reusability of the catalyst with best catalytic activity was also studied. [ABSTRACT FROM AUTHOR]