Na ₂ MSiO ₄ (M = Ca, Mg, and Zn) Silicates as Solid‐Base Catalysts for Dimethyl Carbonate Synthesis via Transesterification

Na ₂ MSiO ₄ (M = Ca, Mg, and Zn) silicate solid‐base catalysts were synthesized by a solid‐state reaction and evaluated for dimethyl carbonate (DMC) synthesis via the transesterification of ethylene carbonate (EC) with methanol (MeOH). The three catalysts exhibited distinct structural characteristics and surface basicities, with Na ₂ CaSiO ₄ showing the highest total basicity and the largest amount of strong basic sites, consistent with its superior catalytic performance. Reaction conditions were further optimized using single‐factor experiments combined with a Box–Behnken response surface design. Under the optimized conditions of a catalyst amount of 5.5 wt%, a MeOH/EC molar ratio of 10.7:1, 63 °C, and 30 min, a DMC yield of 84.93% was achieved. Na ₂ CaSiO ₄ retained 86.3% of its initial catalytic activity after ten reuse cycles, and the DMC yield recovered to 82.36% after regeneration by calcination. Kinetic analysis showed that the reaction could be adequately described by a pseudo‐first‐order model under the investigated conditions, with an apparent activation energy of 41.59 kJ·mol ⁻¹ . These results demonstrate the potential of Na ₂ CaSiO ₄ as a recyclable and regenerable solid‐base catalyst for DMC synthesis.