| 摘要 |
PROBLEM TO BE SOLVED: To provide a method for extracting a solvent of gold capable of suppressing the reduction in the extraction rate of gold even upon the use of a circulation process of repeatedly using an extraction solvent.SOLUTION: There is provided a method of recovering gold using a circulation process where an organic extraction agent is repeatedly used, including: an extraction step of contacting a gold-containing acid aqueous solution with an organic extraction agent; a reduction step of contacting the organic extraction agent after the extraction step with a reduction substance-containing aqueous solution having reduction properties; and an extraction agent circulation step of circularly feeding the organic extraction agent after the reduction step as an organic extraction agent in the extraction step, and, in the extraction agent circulation step, an extraction agent management step is included where the concentration of the substance having reduction properties in the organic extraction agent after the reduction upon repeated circulation and use as the organic extraction agent in the extraction step is regulated to the one hard to be acted as a reduction agent. Thus, the reduction of the recovery rate of gold caused by the circulation process can be suppressed.SELECTED DRAWING: Figure 1 |
