This paper is a brief overview of the role
of inducing the nucleated electro winning of copper by using iron electrodes in
electrocoagulation(EC) process. Cyanide compounds are widely used in gold ore
processing plants in order to facilitate the extraction and subsequent
concentration of the precious metal. Owing to cyanide solution employed in gold
processing, effluents generated have high contents of free cyanide as well as
copper cyanide complexes, which lend them a high degree of toxicity. In this
regard, two options for the treatment of cyanide barren solutions has been
used; in two ways; first for cyanide destruction by oxidation with the use of
the EC process, in theory, has the advantage of decomposing cyanide at the
anode and collecting copper simultaneously by a sludge of copper magnetic iron.
In both cases excellent performance can be achieved using the high capacity of
the bipolar iron EC technology. We found that it is possible to
reduce the copper cyanide complex from 720 mg·l-1 to below 10 mg·l-1 within 20 minutes.
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