Extraction and Recovery of Yttrium and Rare Earth Elements

Patent metadata

Field	Value
Publication number	US-2016138133-A1
Application number	US-201514941434-A
Country	US
Kind code	A1
Filing date	Nov 13, 2015
Priority date	Nov 13, 2014
Publication date	May 19, 2016
Grant date	—

Abstract

Methods for extraction and recovery of rare earth elements are disclosed. In one aspect, heap leaching with a leach solution comprising sulfuric acid is used to extract rare earth elements including yttrium and light and heavy rare earth elements.

First claim

What is claimed is:

1 . A method for recovering yttrium and light and heavy rare earth elements by a heap leaching process, the method comprising:
processing ore containing deposits of yttrium and light rare earth elements (Y+LREEs) and deposits of yttrium and heavy rare earth elements (Y+HREEs), wherein the ore contains yttrofluorite; irrigating the ore on a leach pad with a mineral acid leach solution; dissolving the yttrofluorite in the ore in the mineral acid leach solution; and treating the yttrium and heavy rare earth elements in the mineral acid leach solution to recover the yttrium and heavy rare earth elements from the ore.

2 . The method of claim 1 , further comprising treating the light rare earth elements in the mineral acid leach solution to recover the light rare earth elements from the ore.

3 . The method of claim 1 , wherein the processing step comprises crushing the ore into a grain size of approximately 2 mm to approximately 20 mm.

4 . The method of claim 1 , wherein the processing step comprises crushing the ore into a grain size of approximately 12.5 mm.

5 . The method of claim 1 , wherein the mineral acid leach solution comprises hydrochloric acid.

6 . The method of claim 1 , wherein the mineral acid leach solution comprises sulfuric acid.

7 . The method of claim 6 , wherein the mineral acid leach solution comprises from approximately 5.0% V/V sulfuric acid to approximately 10.0% V/V sulfuric acid.

8 . The method of claim 6 , wherein the mineral acid leach solution comprises 8.3% V/V sulfuric acid.

9 . The method of claim 1 , wherein the irrigating step is conducted for up to approximately three months.

10 . The method of claim 1 , wherein the irrigating step is conducted at ambient temperature.

11 . A method for heap leaching yttrium and light and heavy rare earth elements, the method comprising:
crushing ore from a rock formation containing yttrofluorite or other acid soluble yttrium and rare earth element (Y+REE) containing minerals, wherein the ore contains a deposit of light rare earth elements (LREEs) and a deposit of heavy rare earth elements (HREEs), wherein yttrofluorite hosts at least some of the yttrium and heavy rare earth elements (Y+HREEs); heaping the ore on a leach pad; allowing a mineral acid leach solution to permeate the ore to dissolve the yttrofluorite in the rock formation; and separating the yttrium and heavy rare earth elements in the mineral acid leach solution to recover the yttrium and heavy rare earth elements from the ore.

12 . The method of claim 11 , further comprising separating the light rare earth elements in the mineral acid leach solution to recover the light rare earth elements from the ore.

13 . The method of claim 11 , wherein the crushing step comprises crushing the ore into a grain size of approximately 2 mm to 20 mm.

14 . The method of claim 11 , wherein the crushing step comprises crushing the ore into a grain size of approximately 12.5 mm.

15 . The method of claim 11 , wherein the mineral acid leach solution comprises hydrochloric acid.

16 . The method of claim 11 , wherein the mineral acid leach solution comprises sulfuric acid.

17 . The method of claim 16 , wherein the mineral acid leach solution comprises from approximately 5.0% V/V sulfuric acid to approximately 10.0% V/V sulfuric acid.

18 . The method of claim 16 , wherein the mineral acid leach solution comprises 8.3% V/V sulfuric acid.

19 . The method of claim 11 , wherein the allowing step is conducted for up to approximately three months.

20 . The method of claim 11 , wherein the mineral acid leach solution permeates the ore at approximately room temperature.

Assignees

• Univ Texas

Inventors

• Pingitore Jr Nicholas E

Classifications

• C22B3/08

  Sulfuric acid {, other sulfurated acids or salts thereof} · CPC title

• C22B59/00 Primary

  Obtaining rare earth metals · CPC title

• C22B1/24

  Binding; Briquetting {; Granulating} · CPC title

• C22B3/10

  Hydrochloric acid {, other halogenated acids or salts thereof} · CPC title

• C22B61/00

  Obtaining metals not elsewhere provided for in this subclass (iron C21) · CPC title