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This work presents the results of a study on the simultaneous destruction of cyanide and recovery of copper from alkaline aqueous solutions in a continuous flow electrochemical reactor that consists of a reticulated vitreous carbon anode and two graphite cathodes. The experiments were carried out using different electrolytes ͑e.g., NaOH, NaCl, and Na 2 SO 4 ). The concentrations of total cyanide and copper were measured as a function of electrolysis time at various applied cell potentials and flow rates. Under the best experimental conditions, the total cyanide concentration was reduced from 590 ppm to less than 2 ppm while recovering 98.6% of the copper present in solution simultaneously with this electrochemical system.Metal cyanide compounds are used extensively in the electroplating and metal finishing industries. The process wastewater from these operations often contains cyanide and precious metals. Conventional treatment processes for these wastewaters may consist of oxidation of cyanide by chlorine gas or by hypochlorite followed by removal of cuprous and cupric ions as hydroxide precipitates. This method requires careful control of the pH of the processing solution and a dose of hypochlorite in excess of the stoichiometric quantity required by the reaction. The resulting sludge is difficult to handle because it contains copper hydroxides which can be subjected to easy dissolution giving rise to a copper-rich solution.During the course of chlorination of cyanide solution by chlorine gas or by sodium hypochlorite in alkaline solutions, 1 cyanide is converted to CNO Ϫ , CO 2 , N 2 , and NH 4 ϩ . The cost of this chlorination process is high and workers must be extra careful in handling these dangerous and extremely corrosive chemicals. Moreover, the drawback is that the metal-cyanide complex in a high concentrate free cyanide solution cannot be adequately treated. Destruction of cyanide by incineration of cyanide waste or by thermal hydrolysis are alternative methods. 2 The cost of incineration, including equipment, maintenance, and operation, is also high. The cost of thermal hydrolysis is about 10-35% of the cost of conventional chlorination treatment, however this method does not permit the recovery of heavy metal ions from waste electroplating solutions.

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