SIMULTANEOUS REMOVAL OF CYANIDES AND COPPER IN AN ELECTROCHEMICAL REACTOR - EFFECTS OF AGITATION

摘要

The use of stainless steel electrodes for cyanide destruction and copper electrodeposition from diluted wastewater was found to be technically and economically feasible. The rate of cyanide decomposition was enhanced by the presence of Cu, due to in situ deposition of a Cu oxyhydroxide electrocatalytic film on the anode. The relative Cu~(2+)/Cu~+ ratio in the electrocatalytic film varied with the mixing conditions. The necessary minimum and maximum stirring intensities, at which shearing of the film occurred, were quantified in terms of the shear rate y and the shear stress τ acting on the anode surface. The mode of agitation influenced also the relative rates of cyanide and copper elimination. Hydraulic stirring promoted copper electrodeposition to a greater extent than mixing by compressed air, the later leading to slightly higher rates of cyanides removal.