RARE EARTH ELEMENT RECOVERY METHOD

WIPO Patent Application WO/2013/085052

A1

　Provided is a rare earth element recovery method in which rare earth elements, particularly including Nd and Dy, are efficiently leached from a leaching raw material containing rare earth elements, and then separated and recovered.　A rare earth element recovery method comprising: a leaching step in which an acidic slurry, which is a leaching raw material containing raw earth elements, is maintained under prescribed conditions and subjected to a rare earth element leaching process, then subjected to solid-liquid separation, and a leached solution containing rare earth elements is obtained; and a separation step in which rare earth elements are separated and recovered from the leached solution obtained. Therein: the leaching raw material contains, in the solid components (S) thereof, 4-15 mass% Ca in the form of CaO, and 2-13 mass% Ti in the form of TiO2; an acid solution is an acid solution of hydrochloric acid and/or nitric acid; the leaching process carried out during the leaching step is a warm extraction carried out under heat and pressure conditions of 160-300°C and 0.65-10MPa, and rare earth elements are leached together with Ca in said leaching step.

SUGITA KAORU (JP)
OTA YUJI (JP)
TAGUCHI YOSHIHIRO (JP)
TAKEDA SATOSHI (JP)

PCT/JP2012/081856

June 13, 2013

December 07, 2012

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NIPPON LIGHT METAL CO (JP)

C22B59/00; B09B3/00; C02F11/00; C02F11/12; C22B3/04; C22B3/20; C22B3/26; C22B3/44; C22B7/00; C22B26/20

JP2000313928A	2000-11-14
JPH09184028A	1997-07-15
JPH10212532A	1998-08-11

SASAKI Kazuya et al. (JP)
Kazuya Sasaki (JP)

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