ELECTROCHEMICAL PRODUCTION OF CUPROUS-OXIDE AND METALLIC NICKEL IN A 2-COMPARTMENT CELL

The purpose of the present investigation was to develop an electrochemical process to obtain simultaneously cuprous oxide powder and metallic nickel in a two-compartment cell. Nafion(R) 901 bimembrane (Dupont, USA) was employed to separate the compartments to avoid the diffusion of nickel ions from the catholyte to the anolyte. A continuous addition of sodium hydroxide solution to the anodic compartment was necessary to form in situ the cuprous oxide by chemical reaction with the cuprous chlorocomplexes generated at the anode. As an anode system, a titanium basket filled with copper scrap wire was utilized. The anodic operating conditions were: NaCl 250 g dm-3, pH 10, 80-degrees-C, c.d. 6 A dm-2 and current concentration 0.4 A dm-3. The cathodic parameters were: Ni2+ 74 g dm-3, H3BO3 30 g dm-3, sodium lauryl sulphate 0.5 g dm-3, coumarin 0.15 g dm-3, pH 2, 50-degrees-C, c.d. 6 A dm-2. Good quality red-violet cuprous oxide powder, meeting ASTM specifications D912-65 to be used in antifouling paints and metallic nickel (> 99.96% Ni) was obtained.