Title:
METHOD FOR SEPARATING AND RECOVERING Y AND Eu
Document Type and Number:
Japanese Patent JP3950968
Kind Code:
B2
Abstract:
PROBLEM TO BE SOLVED: To separate/recover Y (yttrium) and Eu (europium) from a waste 3 wavelength phosphor.
SOLUTION: The Y-Eu separation recovery method includes: a 1st stage of subjecting a waste mixture to sulfuric acid water solution treatment to discharge a Y-Eu-containing leach liquor; a 2nd stage of regulating its pH to about 0.5 to 1.1; a 3rd stage of subjecting it to extraction treatment with an organic solvent so as to be separated into a Y-containing organic phase and an Eu-containing water phase; a 4th stage of subjecting the organic phase to sulfuric acid treatment to discharge the Y-containing organic phase and performing hydrochloric acid treatment to discharge a Y-containing hydrochloric water solution; a 5th stage of adding oxalic acid to the hydrochloric acid water solution to filter away precipitates: a 6th stage of heating the Y-containing filtered product into Y2O3 and regulating the pH of the Eu-containing water phase obtained by the 3rd stage to about 1.5 to 2.2; a 7th stage of performing extraction with an organic solvent, separating the Eu-containing organic phase and performing hydrochloric acid treatment to discharge the Eu-containing hydrochloric acid water solution; and an 8th stage of adding oxalic acid to the hydrochloric acid water solution to filter away precipitates and to discharge an Eu-containing compound and performing firing under heating to discharge Eu2O3.
Inventors:
Mikiya Tanaka
Tatsuya Enao
Tatsuya Enao
Application Number:
JP2003156295A
Publication Date:
August 01, 2007
Filing Date:
June 02, 2003
Export Citation:
Assignee:
National Institute of Advanced Industrial Science and Technology
International Classes:
B01D11/04; C22B59/00; C01F17/00; C22B3/26; C22B3/44; C22B7/00; (IPC1-7): C22B59/00; B01D11/04; C01F17/00; C22B3/26; C22B3/44; C22B7/00
Domestic Patent References:
| JP2000192167A | ||||
| JP62278238A | ||||
| JP8333642A |