Modeling of a Two-Phase Electrochemical Reactor for the Fluorination of Organic Compounds. 2. Multiple Steady States

A three-cell, continuous-flow electrochemical reactor is numerically simulated, revealing multiple steady states in terms of production rate. The bipolar electrochemical reactor fluorinates organic compounds in liquid solution in parallel flow cells, accompanied by the generation of hydrogen gas. The mathematical model of two-phase flow, phase equilibrium, gas-phase molecular association, and thermal energy considerations by Drake et al. (Ind. Eng. Chem. Res. 2001, 40, 3109; J. Electrochem. Soc. 1998, 145, 1578) is extended to address interactive multiple cells. Necessary model extensions include intercell heat transfer through the bipolar electrodes, inlet flow-distributor connectivity, and serial current redistribution. Multiphase heat transfer, among these other cell-to-cell interactions, affects the occurrence of multiple states and profiles within differently operating parallel cells. A trifurcation point occurs at 17.3 V in the operating curve of total current versus applied potential. Here, this th...