Lithium-rich metallurgical slag

Patent metadata

Field	Value
Publication number	US-11603579-B2
Application number	US-201716069333-A
Country	US
Kind code	B2
Filing date	Jan 4, 2017
Priority date	Jan 12, 2016
Publication date	Mar 14, 2023
Grant date	Mar 14, 2023

Abstract

The present invention concerns a slag composition having a high lithium content, suitable as additive in the manufacture of end-user products, or for the economic recovery of the contained lithium.The lithium concentration indeed compares favorably with that of spodumene, the classic mineral mined for lithium production. This slag is characterized by a composition according to: 3%<Li2O<20%; 1%<MnO<7%; 38%<Al2O3<65%; CaO<55%; and, SiO2<45%.

First claim

The invention claimed is:

1. A Li 2 O bearing metallurgical slag comprising Al 2 O 3 , SiO 2 , CaO, and MnO, wherein the by-weight composition is as follows:
8%≤Li 2 O≤11.6%;
1.2%≤MnO≤6.7%;
39%≤Al 2 O 3 <55%;
2.5%≤CaO<25%; and
15%≤SiO 2 ≤36.4%,
wherein a total cobalt content in the Li 2 O bearing slag is 0.1%≤Co≤0.9%.

2. The Li 2 O bearing metallurgical slag of claim 1 , wherein the SiO 2 concentration is greater than or equal to 15% and lower than 25%.

3. The Li 2 O bearing metallurgical slag of claim 1 , wherein the sum of the Al 2 O 3 , SiO 2 , CaO, MnO, and Li 2 O concentrations is higher than 80%.

4. The Li 2 O bearing metallurgical slag of claim 1 , wherein the by-weight composition meets the following ranges: 8.2%≤Li 2 O≤11.6%, 39%<Al 2 O 3 <48.4%, 2.5%≤CaO<22.8%; and 18.9%≤SiO 2 <36.4%.

5. The Li 2 O bearing metallurgical slag of claim 1 , wherein the by-weight composition is as follows:
8.1%≤Li 2 O≤11.6%;
1.2%≤MnO≤6.7%;
39%≤Al 2 O 3 <48.4%;
19.3%≤CaO<22.8%; and
21%≤SiO 2 ≤36.4%,
wherein a total cobalt content in the Li 2 O bearing slag is 0.1%≤Co≤0.9%.

6. A smelting process for recovering Li 2 O from spent lithium-bearing batteries, wherein the recovered Li 2 O is present in slag produced by the smelting process in an amount of at least 8 wt % of the metallurgical slag composition, the process comprising
feeding spent lithium-bearing batteries, their components or their scraps to a smelter, the smelter containing a molten bath comprising a slag layer residing on top of a metal alloy layer; and
introducing oxygen to the molten bath in an amount selected to influence the composition of the metal alloy and the slag, wherein the yield of Co in the metal alloy is at least 95% versus total elemental input to the smelter, the content of Co in the slag is less than 1 wt % of the total slag composition, and the contents of MnO, Al 2 O 3 , CaO, and SiO 2 in the slag are as follows:
1.2%≤MnO≤6.7%;
39%≤Al 2 O 3 <55%;
2.5%≤CaO<25%; and
15%≤SiO 2 ≤36.4%.

7. The process of claim 6 , wherein the total cobalt content in the Li 2 O bearing slag is 0.1%≤Co≤0.5%.

8. The process of claim 6 , wherein the aluminum content in the spent batteries is about 6%.

9. The process of claim 6 , wherein the carbon content in the spent batteries is about 20% to 25%.

10. The process of claim 6 , wherein more than 50% of the lithium reports to the slag.

11. The process of claim 6 , wherein about 38 Nm 3 O 2 per ton of batteries is supplied to the furnace to provide heat to the furnace.

Assignees

• Umicore Nv

Inventors

• Quix Maarten
• Van Horebeek David
• Suetens Thomas

Classifications

• C22B7/04 Primary

  Working-up slag · CPC title

• Y02P10/20

  Recycling · CPC title

• C03C3/062

  with less than 40% silica by weight · CPC title

• C22B26/12 Primary

  Obtaining lithium · CPC title

• C03C3/087

  containing calcium oxide, e.g. common sheet or container glass · CPC title