Tank electrolyzer

Typical pilot process conditions are Reactor 4001 steel enamel tank. Electrolyzer -10 bipolar electrodes with a surface of 0.9 m2/300 A. A suspension of 1 kmol MnS04 H20 in 535 kg H2S04 [55-60%] at 85 °C is circulated from the tank to the electrolyzer. 

This assembly is one of several connecting assemblies in the system. It connects the pressure tank, electrolyzer and bubbler and includes a check valve, a pressure gauge, and an on/off valve. Stainless steel Yor-Lok tube fittings are used throughout with %" stainless steel tubing. 

Cost was an important consideration for us in the development of our experimental solar hydrogen system, so a PEM electrolyzer was discounted in favor of a low pressure alkaline tank electrolyzer. High pressure and high temperature electrolyzers were also evaluated. These were discounted due to higher amounts of energy consumed and the need for more intensive monitoring of the system. 

Perchlorates, Concentrated solutions of sodium chlorate are electrolyzed to produce sodium perchlorate [7601 -89-0] NaClO (see Perchloric ACID AND perchlorates). The electrolytic cells for perchlorate production are usually simple tank electrolyzers. Anode materials are limited to platinum, platinum-clad titanium, or lead dioxide on graphite or titanium. The cathodes are generally mild steel. Cell feed solutions may contain 600 g/L of NaClO. Production of very high (1000 g/L or more) concentrations of NaClO is achieved by resaturating partially converted electrolyte with NaQO and continuing the electrolysis to minimum final NaClO concentrations. A mechanism of perchlorate formation has been proposed involving the reaction of chlorate ion and an absorbed active oxygen species at the anode (38,39). 

Mathematical solution depends on the boundary conditions governed by the geometry of the reactor system. We will confine our attention to plate electrodes. Electrochemical reactors can be divided into two categories tank electrolyzers and channel flow electrolyzers. 

FIGURE 5.18. Approximations during the calculation of primary current distribution in a tank electrolyzer, (a) effect of the side walls (b) effect of the rear walls. 

EXAMPLE 5.3 Primary Current Distribution in a Tank Electrolyzer ... 

THE PROBLEM A tank electrolyzer of 0.3 m capacity is designed to contain ten pairs of electrodes. The interelectrode gap is 4 cm the electrodes are 3 cm from the side walls. Initial design will try to achieve a good primary current distribution by ensuring that the current at the inner electrode surface is at least 95% of the total current and that the latter is at least 95% of the total current for the widest possible electrodes. If the tank length is 80 cm, estimate appropriate dimensions for the electrodes. 

THE PROBLEM A tank electrolyzer is to be scaled up from square electrodes with an area of 10 cm to electrodes with an area of 100 cm. The... 

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