Production of Copper Powders by Alternating Current Polarization of a Copper–Titanium Electrode Pair

Abstract— The possibility of obtaining copper powders using alternating current of industrial frequency is shown. The electrochemical circuit consisted of two cells connected in parallel. A copper–titanium electrode pair was installed in each cell. The electrolyte was an aqueous solution containing copper(II) sulfate. In cell 1, during electrolysis, the copper electrode dissolves in the positive half-cycle with the formation of Cu²⁺, which are reduced on the titanium electrode to Cu⁰ in the form of a dispersed powder. In cell 2 in this half-cycle, the electrolysis does not occur. When the direction of the current is changed, electrolysis occurs only in cell 2. It was found that when the current density changes in the range of 10–75 kA m^–2, the current efficiency of Cu⁰ in each cell increases from 31 to 85.2%. When the concentration of Cu²⁺ varies within 5–10 g L^–1, the current efficiency of Cu⁰ in each cell increases to 84.2%. As a result of the process, ultrafine copper powders are formed. Scanning electron microscopy has shown that the average particle size of copper powders does not exceed 1 µm.