Dimethyl carbonate (DMC) is a valuable eco-friendly compound which can be sustainable produced from CO₂. Its rapid increase in demand is driven by the fast growth of its wide-ranging end-use industries (e.g. polycarbonates, solvent, pharmaceutical, and the lithium-ion battery industries). DMC can be produced in different ways, but the indirect alcoholysis of urea with ethylene- or propylene glycol is a very promising route. The trans-esterification of the ethylene- or propylene carbonate with methanol, leading to DMC, plays a key role in the energy efficiency of the process, being the main hurdle when it is performed using an excess of methanol due to the DMC-methanol azeotrope that requires expensive separation steps.

This work proposes a new process in which the trans-esterification reaction takes place at an excess of propylene carbonate instead of methanol, such that the costly separation of DMC-methanol azeotrope is avoided and high purity DMC (>99.8% wt) can be produced. The newly proposed process is optimally designed. After heat integration, the energy requirement is only 2.64 kW h/kg DMC, which is about 35% lower than best reported figure for the classic process. The dynamics and control of the new process is also provided, and the stability of the process is proven for production changes of ±10% from the nominal rate of 32 ktpy DMC.

碳酸二甲酯（DMC）是一种有价值的生态友好型化合物，可以由CO ₂可持续生产。其广泛的最终用途行业（例如聚碳酸酯，溶剂，制药和锂离子电池行业）的快速增长推动了需求的快速增长。DMC可以以不同的方式生产，但是尿素与乙二醇或丙二醇的间接醇解是非常有前途的途径。碳酸亚乙基酯或碳酸亚丙酯与甲醇的酯交换反应，导致DMC，在该过程的能源效率中起关键作用，由于使用DMC-甲醇共沸物而使用过量的甲醇，这是主要的障碍。这需要昂贵的分离步骤。

这项工作提出了一种新方法，其中酯交换反应是在过量的碳酸亚丙酯而不是甲醇下进行的，从而避免了DMC-甲醇共沸物的昂贵分离，并可以生产高纯度DMC（> 99.8 wt％） 。对新提出的过程进行了优化设计。热集成后，能量需求仅为2.64 kW h / kg DMC，比经典方法的最佳报告数字低约35％。还提供了新工艺的动力学和控制功能，并且对于32 ktpy DMC的标称速率±10％的生产变化，已证明该工艺的稳定性。