| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a solvent extraction method which is used in a wet copper-refining process comprising the steps of chlorine-leaching a raw copper material, reducing the obtained aqueous solution of the chloride, separating copper through a solvent extraction method and electrolytically extracting the copper ion, comprises an extraction step and a back extraction step, and further includes decreasing the concentration of copper remaining in the extractant formed after the back extraction step to a minimum value, by bringing an organic phase formed of an extractant containing a monovalent copper ion obtained in the extraction step into contact with an aqueous phase formed of a waste liquid of a copper electrolysis cathode chamber and mixing them to back-extract copper in the back extraction step. <P>SOLUTION: When bringing the aqueous solution of the chloride after having been reduced into contact with an extractant containing tributyl phosphate and mixing them in the extraction step, and subsequently bringing the organic phase formed of the extractant containing the monovalent copper ion obtained in the extraction step into contact with the aqueous phase formed of the waste liquid from the copper electrolysis cathode chamber and mixing them to back-extract copper in the back extraction step, this solvent extraction method includes controlling an oxidation reduction potential (versus silver/silver chloride electrode) of the aqueous phase after the back extraction step to 300 to 400 mV. <P>COPYRIGHT: (C)2009,JPO&INPIT</p> |
