Cell voltage perchlorate

The anode and cathode chambers are separated by a cation-permeable fluoropolymer-based membrane (see Membrane technology). Platinum-electroplated high surface area electrodes sold under the trade name of TySAR (Olin) (85,86) were used as the anode the cathode was formed from a two-layer HasteUoy (Cabot Corp.) C-22-mesh stmcture having a fine outer 60-mesh stmcture supported on a coarse inner mesh layer welded to a backplate. The cell voltage was 3.3 V at 8 kA/m, resulting ia a 40% current efficiency. The steady-state perchloric acid concentration was about 21% by weight. 

Diaphragm cells (with plastic cloth diaphragms) are used with platinum anodes and silver cathodes. A silver cooler is utilized to remove the heat of reaction. The cell voltage is 4.4 V, the yield based on electricity supplied is 60%. Part of the electrolyte is continuously taken off and concentrated to ca. 70% perchloric acid. 

Technical perchlorate cells are operated at up to 5 kA m-2, the cell voltage then being up to 6.5 V (due to high ohmic losses in the cell) leading to a specific energy use of 2500-3000 kWh per ton NaClC>4. But it must be noted that the corresponding values for the educt sodium chlorate should be added [38]. 

The electrochemical procedure for the synthesis of the complex was similar to those described by Tuck [559]. The cell was a 100-cm3 tail-form beaker fitted with a rubber bung through which the electrochemical leads enter the cell. The indium anode was suspended from a platinum wire and the cathode was a platinum wire. [(pySe)2] (0.31 g) was dissolved in acetonitrile and a small amount of tetraethylammonium perchlorate was added to the solution as a current carrier. An applied voltage of 10 V produced a current of 15 mA. During the electrolysis nitrogen gas was bubbled through the solution to provide an inert atmosphere and also to stir the solution phase. After 1 hr of reaction 70 mg of metal had been dissolved from the anode (Ey = 1.1). 

Figure 23.16. Equihbriijm soluble platinum as a function of potential. Solid circles, 80 °C, 2-3 mn platinum particles of a 46 wt% Pt/C powder (Tanaka) in 0.5 M H2S04[33] triangles, 23 C Pt wire in 0.57 M perchloric acid [70]. (Reprinted by permission of ECS— The Electrochemical Sociely, from Wang X, Kumar R, Myersz DJ. Effect of voltage on platinum dissolution relevance to pol3raier electrolyte fuel cells.)...

Figure 30.52 Eagle Richer resewe primary manganese dioxide-magnesium perchlorate battery capacity retention in activated state, shown to 1.0 V/cell end-voltage (Courtesy of Eagle Richer)...

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