Reactions and transport phenomena at surfaces. Water research program biennial progress report for the period March 15, 1966--March 15, 1968

Experimental Verification of a Simplified Model for Porous Electrode Electrochemical Reactors

“…It can be estimated from Eq. [38] and [39] that L ,.-0.14 cm and v --~ 1.8 • 10-2 cm sec -1 for this application. Consequently the required cross-sectional area would be A ,., 2.5 X 104 cm 2, so that the physical dimensions of the reactor would need to be approximately 1.5m on a side by ~1.5 mm thick.…”

“…The limiting behavior predicted by Eq. [33] has been observed in other studies of porous electrode systems (4,38). Equation [13] predicts that a plot of In vs. U -2/z will be linear with a zero intercept.…”

“…The optimum electrode length and linear flow rate, calculated from Eq. [38] and [39], are 2.3 cm and 1.1 cm sec -1, respectively. Consequently the required volume flow rate demands use of a cross-sectional area A ,~ 400 cm% Thus a compact porous electrode device is capable of treating a large volume of liquid in applications of this type.…”

“…It is clear from Eq. [38] and [39] that the optimum reactor length and flow rate will depend on the allowable potential difference between the upstream and downstream faces of the electrode (hr and on the concentration of the electroactive species (Cb). The other quantities in Eq.…”

“…The other quantities in Eq. [38] and [39] describe the properties of the electrode and the electrolyte and the desired (CE). Bennion and Newman (22) and Newman and Tiedemann (5) discuss alternative relations that could be used for design and optimization of porous electrodes operating under limiting current conditions for (CE) ~ 1.…”