Title:
METHOD FOR RECOVERING RARE EARTH METALS
Document Type and Number:
WIPO Patent Application WO/2012/137495
Kind Code:
A1
Abstract:
Provided is a method for recovering rare earth metals which enables rare earth metals to be selectively recovered in an easy and reliable manner from tin slag containing rare earth metals, radioactive substances, iron, aluminum, and the like. The present invention is provided with: an inorganic acid leaching step (2) for performing water granulation or mechanical pulverization of tin slag discharged during tin smelting, and dissolving the product thereof using an inorganic acid; a first oxidation and neutralization step (3) and a filtration step (4) for adding an oxidizing agent and neutralizing agent to a solution of the tin slag, and adjusting the solution to a first condition in which radioactive substances precipitate and rare earth metals and iron do not precipitate, and then precipitating and removing radioactive substances; a second oxidation and neutralization step and filtration step (5, 6) for adding an oxidizing agent and neutralizing agent to a neutral solution to be discharged, and adjusting the solution to a second condition in which iron precipitates and rare earth metals do not precipitate, and then filtering and removing the precipitated iron; and an organic solvent extraction step (7), a strip step (8), a precipitation step (9), a precipitation washing step (10), and a drying/sintering step (11) for recovering the rare earth metals in the filtered neutral solution.
Inventors:
MOCHIDA HIROMI (JP)
SUYA CHIKARA (JP)
MIYAMOTO TAKAHIRO (JP)
IIJIMA DAISUKE (JP)
SUYA CHIKARA (JP)
MIYAMOTO TAKAHIRO (JP)
IIJIMA DAISUKE (JP)
Application Number:
PCT/JP2012/002351
Publication Date:
October 11, 2012
Filing Date:
April 04, 2012
Export Citation:
Assignee:
MITSUBISHI MATERIALS TECHNO CO (JP)
MOCHIDA HIROMI (JP)
SUYA CHIKARA (JP)
MIYAMOTO TAKAHIRO (JP)
IIJIMA DAISUKE (JP)
MOCHIDA HIROMI (JP)
SUYA CHIKARA (JP)
MIYAMOTO TAKAHIRO (JP)
IIJIMA DAISUKE (JP)
International Classes:
C22B59/00; B09B3/00; C02F1/26; C02F1/62; C02F1/72; C22B3/26; C22B7/04
Foreign References:
| JP2011001584A | 2011-01-06 | |||
| JP2008297608A | 2008-12-11 |
Attorney, Agent or Firm:
SHIMIZU, CHIHARU (JP)
Spring water Chiharu (JP)
Spring water Chiharu (JP)
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