Numerical Evaluation and Theoretical Insights of In-Situ Water Removal in DME Synthesis via CO2 Hydrogenation

Dimethyl ether (DME) is a promising alternative fuel, particularly when synthesized via CO2 hydrogenation. Conventional processes are limited by water formation, which reduces conversion and selectivity. This study develops a kinetic model in MATLAB to evaluate the impact of in situ water removal on DME synthesis. Model validation against literature data showed excellent agreement (R² ˜ 0.999). Results indicate that partial water removal of around 30% is sufficient to enhance DME production by ˜ 37%, with diminishing gains beyond this point. The use of 2-cyanopyridine (2-CP) is theoretically discussed as an alternative for selective membranes for water removal as it gets formed. Even though 2-CP offers a conceptually simple alternative, regeneration and safety issues must be addressed. Overall, the numerical findings highlight that partial water removal can significantly intensify DME synthesis, and that the approach of using 2 CP requires further experimental investigation to assess its practical feasibility. Overall, the present work provides a methodological basis for evaluating and optimizing intensified DME synthesis routes from renewable CO2.