Method for producing copper and apparatus for producing copper

Abstract

A method for producing copper includes a first step of dissolving copper by adding a copper-containing material to a solution containing an oxidant, and a second step of depositing copper on a surface of a cathode by bringing a solution (A) containing the oxidant in a reduced state into contact with a solution (B) containing copper dissolved therein with a separator provided between the solution (A) and the solution (B), arranging an anode in the solution (A), arranging the cathode in the solution (B), and applying a voltage to both the electrodes, while the oxidant contained in the solution (A) is regenerated, in which the oxidant has a standard electrode potential of 1.6 V or less.

Description

TECHNICAL FIELD[0001]The present invention relates to a method for producing copper by electrolytic refining and an apparatus for producing copper.BACKGROUND ART[0002]In general, copper and copper alloys are metals that are in high demand like iron, aluminum, and so forth. It is thus important to collect, for example, discarded electric wires and printed circuit boards in home appliances and recover copper from copper scraps that contain copper from the viewpoint of protecting resources.[0003]However, low-purity copper is often discarded without being reused in the present circumstances for economic reasons. Furthermore, in the recycling of copper from electric wires, there has been copper that cannot be recovered. Although in some cases copper is recycled in large-scale smelters, a certain amount of waste is required for recycling, and transportation costs are high.[0004]For example, when copper is recovered from copper scraps collected from markets, in the case of power cables, co...

AI Technical Summary

Benefits of technology

The present invention offers a cost-effective method for producing pure copper through a wet process without creating environmental concerns or waste liquid.

Problems solved by technology

However, low-purity copper is often discarded without being reused in the present circumstances for economic reasons.

Furthermore, in the recycling of copper from electric wires, there has been copper that cannot be recovered.

Although in some cases copper is recycled in large-scale smelters, a certain amount of waste is required for recycling, and transportation costs are high.

For communication cables, in the case of thick cables, copper can also be separated and recovered by stripping sheath resins, whereas in the case of thin cables, workloads are excessively heavy; thus, such a recovery method cannot be performed.

However, small amounts of resins are left on the surface of copper; thus, resins need to be burned away by firing.

Although the recovery of copper by a dry process as described above is a simple process, carbon dioxide is generated by the combustion of resins to lead to high environmental loads.

Moreover, metallic copper recovered has a low purity, depending on the purity of raw-material copper scraps collected from markets.

However, oxygen is generated on an anode in the wet process; thus, the wet process has a disadvantage that power consumption during electrolysis is inevitably increased.

Thus, the use of chlorine gas requires specialized management techniques.

This results in lower power consumption than ever before.

If the resin reacts with ammonia, ammonia is undesirably consumed.

In addition, there is a problem that impurities in the resin are easily dissolved in the ammonia-alkaline solution.

Images