Experimentally Validated 3D-CFD Analysis of Continuous-Flow\nReactor Configurations for the Electrochemical Trifluoromethylation\nof Caffeine

Electrochemistry\nfor producing pharmaceuticals has been gaining\nprominence in recent times as it offers a safer, greener, and cheaper\nalternative to conventional approaches for some key and difficult\nsynthesis steps, such as trifluoromethylation. However, commercial\napplication of the nanoparticle to a continuous manufacturing facility\nhas many challenges. In this work, we develop 3D high-fidelity CFD\nmodels of various electrochemical reactor geometries for the trifluoromethylation\nof caffeine. The developed model is validated with in-house continuous\nflow trifluoromethylation experiments. The impact of the various process\nvariables, such as the electrode gap, residence time, reactant inlet\nconcentration, pulsation frequency, and duty cycle, on system performance\nis investigated in terms of yield, selectivity, and productivity.\nSeveral reactor configurations are analyzed, such as flat parallel\nplates, annular, serpentine channels, spiral, and 3D-printed electrodes.\nWe find that the electrode gap and residence time greatly impact the\nsystem performance. Lower electrode gaps and longer residence times\ncorrelate to higher productivity. The 3D-printed electrode system\nwas found to give a higher product yield compared with a flat electrode\nsystem. Furthermore, our CFD results show that employing spiral paths\nand serpentine channels offers a higher selectivity (up to 0.41) and\nenhanced productivity (increment of 23% compared with flat parallel\nplates).