Bipolar trickle tower reactor

Bipolar Trickle Tower Reactor British Technology Group Series (<60) of bipolar elements in a column Discontinuous via leaching or removal of the carbon bed No / /... 

Fleischmann, M. and Ibrisagic, Z. (1980) Electrochemical measurements in bipolar trickle tower reactors. Journal of Applied Electrochemistry, 10, 151. 

It is also possible to operate three-dimensional electrodes in a bipolar manner, as in the case of the bipolar trickle tower reactor (Fig. 2.26) where each electrode layer is separated from its neighbour by an insulating mesh. The potential distribution along the height of each layer is non-uniform (Fig. 2.26(b)) and the packing conditions, electrolyte composition and electrolyte flow must be controlled to minimize the bypass current flowing past each layer, within the reactor envelope. Hence, such reactors are best suited to poorly conducting electrolytes. 

Fig, 2-26 The bipolar trickle-tower reactor, (a) A schematic, (b) The potential distribution over a single bipolar layer The electrode is assumed to have a constant potential, while the solution potential, varies with distance down the layer. The driving force for reaction varies with position, being largest near the ends of each electrode... 

The bipolar trickle tower reactor has already been mentioned (Fig. 2 26). Here, the electrolyte falls, under gravity, down a packed column containing a bipolar array of electrodes. In order to maintain trickle flow (and hence, minimize bypass currents) the flow rate is restricted High flow rates cause flooding while tow values result in incomplete wetting of the electrodes. 

A semi-regular array of elements, as in the bipolar trickle-tower reactor (Fig. 2.26). 

Trickle tower reactors containing a number (typically <60) of vertically stacked, bipolar electrode layers have been studied for metal-ion removal at the University of Southampton [41-44]. Earlier studies [41-43] employed layers of hollow carbon cylinders known as Raschig rings (see figure 10a). The relatively low active cathode area per unit reactor volume together with constructional difficulties associated with these packings led to the examination of alternative materials such as felt, particles, foam and perforated plates [44]. 

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