Method for recovering copper
AssigneeHenkel Corporation
InventorsMichael J. Virnig, J. Murdoch MacKenzie
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Abstract
An improved process is described for the recovery of copper from an aqueous feed solution using solvent extraction and electrowinning in which the electrowinning is conducted in a first step wherein the electrolyte is flowing perpendicular to the cathode surface without auxiliary mixing of the electrolyte between electrodes, and a second step wherein the electrolyte is flowing parallel to the cathode surface. In a second embodiment, solvent extraction of copper and solvent extraction of acid are conducted in alternate steps to allow more complete recovery of copper.
Claims36
An improved process for the recovery of copper from an aqueous feed solution by solvent extraction, stripping and electrowinning, the improvement comprising conducting a first electrowinning step in a first electrowinning cell with electrolyte flowing perpendicular to the plane of the electrodes and without auxiliary mixing of electrolyte between the electrodes and conducting a second electrowinning step in a second electrowinning cell with the electrolyte from the first electrowinning step flowing parallel to the cathode surface, whereby the copper concentration of electrolyte after the second electrowinning step is reduced below about 30 g/l.
An improved process for the solvent extraction of copper from an aqueous feed solution, wherein said aqueous feed solution is contacted with a first organic extractant solution to produce a loaded first organic solution enriched in copper and an aqueous solution depleted in copper and enriched in acid, and the loaded first organic solution is contacted with a strong acid strip solution to produce a stripped first organic solution depleted in copper and a pregnant strong acid strip solution enriched in copper, the improvement comprising the additional steps of (1) contacting said aqueous solution depleted in copper and enriched in acid with a second organic extractant solution capable of extracting a mineral acid, (2) separating the phases, to produce a second loaded organic solution enriched in acid and an aqueous solution depleted in acid, (3) contacting said aqueous solution depleted in acid with a second portion of the first organic extractant solution, and (4) separating the phases to produce a loaded organic solution enriched in copper and an aqueous solution further depleted in copper and enriched again in acid.
Dependencies are inferred from the claim text.