Efficient recycling of e-waste by energy landscape inversion

Patent metadata

Field	Value
Publication number	US-2024425948-A1
Application number	US-202418752936-A
Country	US
Kind code	A1
Filing date	Jun 25, 2024
Priority date	Jun 26, 2023
Publication date	Dec 26, 2024
Grant date	—

Abstract

The present invention provides methods for recovering metals, including rare earth metals, from mixed metals. An example is the recovery of metals from electronic waste. The method of separation is based on the inversion and/or lowering of the thermodynamic energy barrier by using one or more stressors applied at appropriate ratios to create lower energy points in the thermodynamic energy landscape of the mixed metals. Example stressors include a) a chemical stress, b) a mechanical stress, c) a thermal stress, d) and electromagnetic radiation and/or light stress, an interfacial stress, and/or a magnetic flux gradient stress.

First claim

What is claimed is:

1 . A method of separation based on inversion and/or lowering of the thermodynamic energy barrier by using one or more stressors applied at appropriate ratios to create lower energy points in the thermodynamic energy landscape, the method comprising using the one or more stressors to separate at least two reclaimable metals from a mixed-metal feed, wherein the one or more stressors is selected from the group consisting of
a) a chemical stress, wherein the chemical stress is selected from the group consisting of an oxidant, an acid, a base, a ligand or chelate, a reactant, a speciating agent, a reducing agent, a nucleophile, and/or an electrophile; b) a mechanical stress, wherein the mechanical stress comprises principle stresses, deviatoric stresses, point forces, and/or body forces; c) a thermal stress; d) an electromagnetic radiation and/or light stress; e) an interfacial stress; and/or f) a magnetic flux gradient stress.

2 . The method of claim 1 , wherein a first one of the one or more stressors is applied as a first asymmetric stress, and wherein the first asymmetric stress is selected from the group consisting of the chemical stress, the mechanical stress or the thermal stress.

3 . The method of claim 2 , wherein a second one of the one or more stressors is applied as a second asymmetric stress, and wherein the second asymmetric stress is selected from the group consisting of the chemical stress, the mechanical stress or the thermal stress.

4 . The method of claim 3 , wherein a first vector of the first asymmetric stress and a second vector of a second asymmetric stress are substantially opposed to one another.

5 . The method of claim 1 , wherein the at least two reclaimable metals are selected from the group consisting of transition metals, other metals, and/or rare earth lanthanide metals.

6 . The method of claim 1 , wherein at least one reclaimable metal of the at least two reclaimable metals is a rare earth lanthanide metal.

7 . The method of claim 1 ,
wherein the at least two reclaimable metals comprise europium, wherein the one or more stressors comprises the chemical stress, wherein the method comprises
i) adding water to the mixed-metal stream to extract the europium;
ii) forming europium particles in the water; and
iii) separating the europium particles from the remaining mixed-metal stream.

8 . The method of claim 1 ,
wherein the at least two reclaimable metals comprise praseodymium, wherein the one or more stressors comprise the chemical stress and the thermal stress, wherein the method comprises
i) adding water to the mixed-metal stream and heating to a temperature above 60° C. to extract the praseodymium;
ii) forming praseodymium particles in the water; and
iii) separating the praseodymium particles from the remaining mixed-metal stream.

9 . The method of claim 8 , wherein the water and the mixed-metal stream are heated to a temperature ranging from 60° C. to 150° C.

10 . The method of claim 1 ,
wherein the at least two reclaimable metals comprise neodymium, wherein the one or more stressors comprises the chemical stress, mechanical stress, and/or the thermal stress, wherein the method comprises
i) combining a solvent and the mixed-metal stream and heating to a temperature ranging from 60° C. to 80° C. to extract the neodymium and/or applying the mechanical stress
ii) forming neodymium particles in the water; and
iii) separating the neodymium particles from the remaining mixed-metal stream,
wherein the solvent comprises water and a base and has a pH ranging from 10 to 13.5.

11 . The method of claim 1 ,
wherein the at least two reclaimable metals comprise praseodymium and neodymium, and the mixed-metal stream comprises at least one additional metal, wherein the one or more stressors comprises the chemical stress, the mechanical stress, and/or the thermal stress, wherein the method comprises
i) adding water to the mixed-metal stream and heating to a temperature above 60° C. and applying the mechanical stress to extract the praseodymium and the neodymium and
ii) forming praseodymium particles and neodymium particles in the water; and
iii) separating the praseodymium particles and the neodymium particles from the remaining mixed-metal stream.

12 . The method of claim 1 ,
wherein the at least two reclaimable metals comprise dysprosium and iron, and the mixed-metal stream comprises at least one additional metal, wherein the one or more stressors comprising the chemical stress, the mechanical stress, and the thermal stress, wherein the method comprises
i) combining a solvent and the mixed-metal stream and heating to a temperature above 40° C. and/or applying the mechanical stress to extract the dysprosium and the iron and
ii) forming dysprosium particles and iron particles in the solvent; and
iii) separating the dysprosium particles and the iron particles from the remaining mixed-metal stream,
wherein the solvent comprises an acid and has a pH ranging from 2.5 to 4.0.

13 . The method of claim 1 ,
wherein the at least two reclaimable metals comprise gallium and indium, and the mixed-metal stream comprises at least one additional metal, wherein the one or more stressors comprises the chemical stress, the mechanical stress, and the thermal stress, wherein the method comprises
i) combining a solvent and the mixed-metal stream and heating to a temperature above 40° C. and/or applying the mechanical stress to extract the gallium and the indium;
ii) forming gallium particles and indium particles in the solvent; and
iii) separating the gallium particles and the indium particles from the remaining mixed-metal stream,
wherein the solvent comprises an acid and has a pH lower than 2.5.

14 . The method of claim 1 ,
wherein the at least two reclaimable metals comprise tantalum, gold, platinum, and/or silver, wherein the one or more stressors comprises electromagnetic radiation, light and/or thermal stress, wherein the method comprises
i) treating the mixed-metal steam in plasma;
ii) separating out the tantalum, gold, platinum, and/or silver from the plasma; and
iii) separating out the remaining mixed-metals from the plasma.

15 . The method of claim 1 ,
wherein the at least two reclaimable metals comprise europium, praseodymium, neodymium, dysprosium, iron, and at least one additional metal, wherein the one or more stressors comprise the chemical stress, the mechanical stress, and/or the thermal stress, wherein the method comprises
i) combining a solvent and the mixed-metal stream and heating to a temperature above 40° C. and applying the mechanical stress to extract the europium, the praseodymium, the neodymium, the dysprosium, and the iron,
ii) forming europium particles, in the solvent; and
iii) separating the europium particles, the praseodymium particles, the neodymium particles, the dysprosium particles, and the iron particles from the remaining mixed-metal stream,
wherein the solvent comprises an acid and has a pH ranging from 2.5-4.

16 . The method of claim 1 ,
wherein the at least two reclaimable metals comprise praseodymium, neodymium, dysprosium, iron, and at least one additional metal, wherein the one or more stressors comprises the chemical stress, the mechanical stress, and/or the thermal stress, wherein the method comprises
i) combining a solvent and the mixed-metal stream and heating to a temperature above 40° C. and applying the mechanical stress to extract the praseodymium, the neodymium, the dysprosium, and the iron,
ii)

Assignees

• Univ North Carolina State

Inventors

• Thuo Martin
• Pauls Alana
• Jamadgni Dhanush

Classifications

• C22B58/00

  Obtaining gallium or indium {(treatment or purification of solutions by liquid-liquid extraction, by ion-exchange or by adsorption C22B3/20)} · CPC title

• C22B3/02

  Apparatus therefor · CPC title

• C22B34/24

  Obtaining niobium or tantalum · CPC title

• C22B11/04

  by wet processes (extraction of metal compounds by leaching in organic solutions C22B3/16; treatment or purification of solutions by liquid-liquid extraction C22B3/26) · CPC title

• C22B59/00 Primary

  Obtaining rare earth metals · CPC title