Efficient recycling of e-waste by energy landscape inversion
AssigneeNorth Carolina State University
InventorsMartin Thuo, Alana Pauls, Dhanush Jamadgni
Life of this patent
Estimating the term…
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.
Claims33
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.
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,
- wherein one of the one or more stressors is 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.
A process of separating a stream of electronic waste (e-waste) metals, wherein the e-waste metals comprise at least two reclaimable metals comprising a first reclaimable metal and a second reclaimable metal, the process comprising:
- a) performing a first extraction/precipitation/separation step of the e-waste metals to produce a product, and a (residual e-waste metals)x, wherein x=1;
- b) performing a next extraction/precipitation/separation step of the (residual e-waste metals)x to produce a productx+1 and a (residual e-waste metals)x+1, and
- c) incrementing x by 1, and repeating step b) until an amount of the at least two reclaimable metals in the (residual e-waste metals)x is less than 5 wt. % of an amount of at least one of the at least two reclaimable metals in the e-waste metals,
- wherein for each of the step a) and the step b) extractions/precipitation/separation steps, a variation is selected from the group consisting of a solvent, a solvent pH, an extraction temperature, an electromagnetic radiation stress, and/or a mechanical stress applied to the e-waste metals and/or (residual e-waste metals)x.
The process of claim 31, further comprising adding the (residual e-waste)5 to a plasma and optionally adding heat to produce a product comprising tantalum and (residual e-waste)6.
A system for separation of a mixed-metal feed based on inversion and/or lowering of the thermodynamic energy barrier by using two or more stressors applied at appropriate ratios to create lower energy points in the thermodynamic energy landscape, the system comprising;
- a) a chamber capable of enclosing
- i) a solution comprising the mixed-metal feed;
- ii) at least a first asymmetric stress and a second asymmetric stress, wherein the first asymmetric stress and the second asymmetric stress are selected from the group consisting of
- 1) 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;
- 2) a mechanical stress, wherein the mechanical stress comprises principle stresses, deviatoric stresses, point forces, and/or body forces;
- or
- 3) a thermal stress;
- b) at least one closable opening through the chamber, wherein the closable opening is capable of providing a pathway for the mixed-metal feed, the chemical stress and any separated metals to enter and leave the chamber;
- c) a variable temperature device capable of supplying the thermal stress;
- and
- d) mechanical device capable of supplying the mechanical stresses
- wherein a content of the chamber comprises the mixed-metal feed, any separated metals, and the solution, and wherein the thermal stress and the mechanical stress applied to the content of the chamber.
A system for separation of a mixed-metal feed based on inversion and/or lowering of the thermodynamic energy barrier by using two or more stressors applied at appropriate ratios to create lower energy points in the thermodynamic energy landscape, the system comprising:
- a) an extractor capable of containing a solution comprising the mixed-metal feed, wherein the extractor comprises a closeable hollow horizontal cylinder;
- b) a rotor placeable in the extractor with a proximal end outside of the extractor and a distal end with attachments within the extractor, wherein the rotor and attachments are capable of providing mechanical stress to the solution when the rotor turns;
- c) a motor connectable to the proximal end of a rotor, wherein the motor is capable of turning the rotor;
- d) a hole at the end of the cylinder when the extractor is closed, through which the proximal end of the rotor transitions from outside the extractor to insiFIG.de the extractor, wherein the hole is located below the midpoint of the cylinder and wherein the proximal end of the rotor is capable of fitting through the hole;
- e) a heat source in the top half of the extractor, wherein the heat source is capable of applying a thermal stress to the solution,
- wherein the system is capable of producing asymmetrical stresses on the solution.
Dependencies are inferred from the claim text.