Method of recovering gold from dilute gold solution
AssigneeJX Nippon Mining & Metals Corporation
InventorsKazuhiro Hatano, Yoshifumi Abe, Eiki Ono, Koji Katsukawa
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Abstract
Disclosed is a method of recovering gold from an aqueous solution having a gold concentration of 10 mg/L or lower, using a plurality of extraction apparatuses for bringing the aqueous solution into contact with an extraction agent, arranged to configure a multi-stage extraction process, the method allowing the aqueous solution to continuously flow from the first-stage extraction process to the next-stage extraction process, while recycling the extraction medium used in each stage twice or more times for the extraction process of the same stage, without back extraction and reduction.
Claims9
A method of recovering gold from an aqueous solution having a gold concentration of 10 mg/L or lower, employing a plurality of extraction apparatuses for bringing the aqueous solution into contact with an extraction solvent arranged to configure a multi-stage extraction process,
- wherein the method allows the aqueous solution continuously flows from a first-stage extraction to a second-stage extraction, while recycling the extraction solvent used in each stage twice or more times within the same stage, without back extraction and reduction;
- wherein in the first-stage extraction, the volume ratio (O/A) of the extraction solvent (Or) and the aqueous solution (Aq) is ⅕ or smaller, and the used extraction solvent is repeatedly used until the concentration of gold in the extraction solvent is 1 g/L or higher;
- wherein in the second-stage extraction gold is repeatedly extracted until the concentration of gold in a post extraction liquid reaches to 0.5 mg/L or below;
- and
- wherein the extraction solvent present in the first-stage is separately prepared and recycled principally within the first-stage of extraction and the extraction solvent present in the second-stage is separately prepared and recycled principally within the second-stage of extraction.
Dependencies are inferred from the claim text.