Spouting bed electrode

Scott [11] compared three types of circulating particulate electrodes for copper recovery from dilute solutions (Fig. 1) spouted (circulating) beds, vortex beds, and moving beds. The beds contained 500— 700 pm spherical copper particles positioned on a stainless steel cathode feeder, and a platinized titanium anode. All electrodes performed similarly in terms of copper recovery current efficiencies. Recovery was found to be more efficient at low pH and high metal concentrations. The spouted bed electrode was preferred on the basis of scaleup. 

V. Jiricny, A. Roy and J. W. Evans, Copper Electrowinning Using Spouted Bed Electrodes Part I. Experiments with Oxygen Evolution or Matte Oxidation at the Anode, Metall. Mater. Trans., B 33, 669-676 (2002). 

Stankovic VD, Stankovic S (1991) An investigation of the spouted bed electrode cell for the electrowinning of metal from dilute solutions. J Appl Electrochem 21 124-129. doi 10.1007/BF01464292... 

Fig. 2.37 Dynamic, particulate-bed electrodes, (a) The inclined two-phase Parel fluid-ized-bed electrode reactor, (b) The moving-bed electrode in a rectangular configuration, (c) The spouting-bed electrode, showing the circulation of a light, rapidly ascending, and a dense, slowly descending, solid phase.

Fig. 1. A schematic of three types of circulating particulate-bed electrodes studied for copper recovery (a) spouted bed (b) vortex bed (c) moving bed. b bed region d diaphragm f feeder e electrolyte flow. (Adapted from [11]).

Porous or particulate fixed bed electrodes have been recognized as the more efficient three-dimensional cathodes used for metal electrodeposition from dilute solutions, mainly due to their uniform effective conductivity of the solid phase. However, electrode clogging due to metal electrodeposition restricts their use as only for very dilute solutimis in which the long operational time would justUy their use [11, 12]. In order to overcome this Umitatimi and make the electrochemical process continuous, mobile electrodes, such as fluidized, spouted, and inclined bed electrodes, were proposed [13-16]. In these electrodes, the conductivity of the... 

An alternative approach is the development of different types of cell design, particularly those utilizing three-dimensional electrodes. This strategy is an attractive one for the treatment of dilute (say <2gdm ) metal-containing liquors, where the increased mass transport and electroactive area of the three-dimensional cathodes is very important in order to sustain a reasonably high current (and, hence, production rate of metal), e.g. cells with packed, spouting or fluidized beds of carbon or metal particles have been operated on a pilot plant and full plant scale. Such cells arc described in detail in Chapters 2 and 7. 

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