Energy-Efficient Reactive Dividing Wall Column Coupled with Pressure-Swing Distillation for Ethyl Methyl Carbonate via Heat Pump Integration

Ethyl methyl carbonate (EMC) has received more and more attention as an important electrolyte. However, even with the enhancement through a reactive dividing wall column (RDWC), which is a method for enhancing the selectivity of EMC in transesterification, the inherent complexity of the reaction still results in the formation of various azeotropic mixtures that are difficult to separate. This study proposes a design for EMC production via RDWC by fully utilizing the recycle in the process, thereby achieving EMC and MeOH as the products. Additionally, based on investigation of the pressure-sensitive characteristics of the MeOH–DMC azeotrope generated during the process, a high-pressure column (HPC) is selected to couple with the RDWC process. The new RDWC-HPC design creates a greener and more sustainable EMC production method. Furthermore, a comprehensive 4E analysis encompassing economics, energy consumption, environmental impact, and exergy was conducted on all processes. The energy efficiency levels of various optimized processes exhibit a stepwise improvement trend, validating the feasibility of technological synergy for enhanced efficiency. Compared to the basic process, the combined process of coupling the heat pump with thermal integration demonstrates optimal comprehensive benefits.