The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.

The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.

Date of Patent:
May. 27, 2025

Filed:

Nov. 04, 2021
Applicant:

University of North Dakota, Grand Forks, ND (US);

Inventors:

Nolan Theaker, Grand Forks, ND (US);

Daniel Laudal, Grand Forks, ND (US);

Christine E. Lucky, Madison, WI (US);

Assignee:

University of North Dakota, Fargo, ND (US);

Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
C01F 17/10 (2020.01); C07C 51/47 (2006.01); C22B 3/00 (2006.01); C22B 3/04 (2006.01); C22B 3/16 (2006.01); C22B 59/00 (2006.01);
U.S. Cl.
CPC ...
C01F 17/10 (2020.01); C07C 51/47 (2013.01); C22B 3/00 (2013.01); C22B 3/04 (2013.01); C22B 3/16 (2013.01); C22B 59/00 (2013.01);
Abstract

A method for recovering rare earth elements (REE) from a leach solution. The method includes determining the concentration of a first plurality of contaminates in the leach solution, adding a first amount of oxalic acid to the leach solution and allowing it to react for a first period of time to form a first precipitant and a first liquor, maintaining the pH of the first liquor between 1.5 and 3 by the addition of an alkali base, removing the first precipitant, adding a second amount of oxalic acid to the first liquor and allowing it to react for a second period of time to form a second precipitant and a second liquor, maintaining the pH of the second liquor between 1.5 and 3 by the addition of the alkali base, and removing the second precipitant.


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