US20210189578A1 - Systems and Methods for Concentrating Ions - Google Patents
Systems and Methods for Concentrating Ions Download PDFInfo
- Publication number
- US20210189578A1 US20210189578A1 US17/126,652 US202017126652A US2021189578A1 US 20210189578 A1 US20210189578 A1 US 20210189578A1 US 202017126652 A US202017126652 A US 202017126652A US 2021189578 A1 US2021189578 A1 US 2021189578A1
- Authority
- US
- United States
- Prior art keywords
- electrode
- ion
- solution
- molecular sieve
- electrochemical cell
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 150000002500 ions Chemical class 0.000 title claims abstract description 156
- 238000000034 method Methods 0.000 title claims abstract description 39
- URGAHOPLAPQHLN-UHFFFAOYSA-N sodium aluminosilicate Chemical compound [Na+].[Al+3].[O-][Si]([O-])=O.[O-][Si]([O-])=O URGAHOPLAPQHLN-UHFFFAOYSA-N 0.000 claims abstract description 72
- 239000002808 molecular sieve Substances 0.000 claims abstract description 59
- 238000004891 communication Methods 0.000 claims abstract description 8
- 239000012530 fluid Substances 0.000 claims abstract description 7
- 239000000243 solution Substances 0.000 claims description 81
- WHXSMMKQMYFTQS-UHFFFAOYSA-N Lithium Chemical compound [Li] WHXSMMKQMYFTQS-UHFFFAOYSA-N 0.000 claims description 47
- 229910052744 lithium Inorganic materials 0.000 claims description 46
- 229910001416 lithium ion Inorganic materials 0.000 claims description 21
- 238000006479 redox reaction Methods 0.000 claims description 20
- HBBGRARXTFLTSG-UHFFFAOYSA-N Lithium ion Chemical compound [Li+] HBBGRARXTFLTSG-UHFFFAOYSA-N 0.000 claims description 18
- 229920000642 polymer Polymers 0.000 claims description 9
- 239000012267 brine Substances 0.000 claims description 7
- HPALAKNZSZLMCH-UHFFFAOYSA-M sodium;chloride;hydrate Chemical compound O.[Na+].[Cl-] HPALAKNZSZLMCH-UHFFFAOYSA-M 0.000 claims description 7
- DGAQECJNVWCQMB-PUAWFVPOSA-M Ilexoside XXIX Chemical compound C[C@@H]1CC[C@@]2(CC[C@@]3(C(=CC[C@H]4[C@]3(CC[C@@H]5[C@@]4(CC[C@@H](C5(C)C)OS(=O)(=O)[O-])C)C)[C@@H]2[C@]1(C)O)C)C(=O)O[C@H]6[C@@H]([C@H]([C@@H]([C@H](O6)CO)O)O)O.[Na+] DGAQECJNVWCQMB-PUAWFVPOSA-M 0.000 description 18
- 229910052708 sodium Inorganic materials 0.000 description 18
- 239000011734 sodium Substances 0.000 description 18
- FAPWRFPIFSIZLT-UHFFFAOYSA-M Sodium chloride Chemical compound [Na+].[Cl-] FAPWRFPIFSIZLT-UHFFFAOYSA-M 0.000 description 8
- 239000000463 material Substances 0.000 description 8
- 238000010586 diagram Methods 0.000 description 7
- 238000005516 engineering process Methods 0.000 description 7
- 238000009830 intercalation Methods 0.000 description 7
- 239000013535 sea water Substances 0.000 description 7
- 229910001415 sodium ion Inorganic materials 0.000 description 7
- 230000002687 intercalation Effects 0.000 description 6
- KWGKDLIKAYFUFQ-UHFFFAOYSA-M lithium chloride Chemical compound [Li+].[Cl-] KWGKDLIKAYFUFQ-UHFFFAOYSA-M 0.000 description 6
- 150000003983 crown ethers Chemical class 0.000 description 5
- 238000004519 manufacturing process Methods 0.000 description 5
- 239000000203 mixture Substances 0.000 description 5
- 238000011084 recovery Methods 0.000 description 5
- WYURNTSHIVDZCO-UHFFFAOYSA-N Tetrahydrofuran Chemical compound C1CCOC1 WYURNTSHIVDZCO-UHFFFAOYSA-N 0.000 description 4
- 238000004146 energy storage Methods 0.000 description 4
- 238000000605 extraction Methods 0.000 description 4
- 229910000399 iron(III) phosphate Inorganic materials 0.000 description 4
- 230000008569 process Effects 0.000 description 4
- 239000011780 sodium chloride Substances 0.000 description 4
- -1 sodium ions Chemical class 0.000 description 4
- FKNQFGJONOIPTF-UHFFFAOYSA-N Sodium cation Chemical compound [Na+] FKNQFGJONOIPTF-UHFFFAOYSA-N 0.000 description 3
- 150000001875 compounds Chemical class 0.000 description 3
- 230000007613 environmental effect Effects 0.000 description 3
- WBJZTOZJJYAKHQ-UHFFFAOYSA-K iron(3+) phosphate Chemical compound [Fe+3].[O-]P([O-])([O-])=O WBJZTOZJJYAKHQ-UHFFFAOYSA-K 0.000 description 3
- 239000002245 particle Substances 0.000 description 3
- 238000004088 simulation Methods 0.000 description 3
- 238000012360 testing method Methods 0.000 description 3
- PVDDBYSFGBWICV-UHFFFAOYSA-N 1,4,8,11-tetraoxacyclotetradecane Chemical compound C1COCCOCCCOCCOC1 PVDDBYSFGBWICV-UHFFFAOYSA-N 0.000 description 2
- CXVOIIMJZFREMM-UHFFFAOYSA-N 1-(2-nitrophenoxy)octane Chemical compound CCCCCCCCOC1=CC=CC=C1[N+]([O-])=O CXVOIIMJZFREMM-UHFFFAOYSA-N 0.000 description 2
- KDMUFHBMXZLDLI-UHFFFAOYSA-N 6,6-dibenzyl-1,4,8,11-tetraoxacyclotetradecane Chemical compound C1OCCOCCCOCCOCC1(CC=1C=CC=CC=1)CC1=CC=CC=C1 KDMUFHBMXZLDLI-UHFFFAOYSA-N 0.000 description 2
- 239000011248 coating agent Substances 0.000 description 2
- 238000000576 coating method Methods 0.000 description 2
- 238000011161 development Methods 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 239000003792 electrolyte Substances 0.000 description 2
- 238000001704 evaporation Methods 0.000 description 2
- 239000002555 ionophore Substances 0.000 description 2
- 230000000236 ionophoric effect Effects 0.000 description 2
- GELKBWJHTRAYNV-UHFFFAOYSA-K lithium iron phosphate Chemical compound [Li+].[Fe+2].[O-]P([O-])([O-])=O GELKBWJHTRAYNV-UHFFFAOYSA-K 0.000 description 2
- 229920001343 polytetrafluoroethylene Polymers 0.000 description 2
- 239000004810 polytetrafluoroethylene Substances 0.000 description 2
- YLQBMQCUIZJEEH-UHFFFAOYSA-N tetrahydrofuran Natural products C=1C=COC=1 YLQBMQCUIZJEEH-UHFFFAOYSA-N 0.000 description 2
- ZMBHCYHQLYEYDV-UHFFFAOYSA-N trioctylphosphine oxide Chemical compound CCCCCCCCP(=O)(CCCCCCCC)CCCCCCCC ZMBHCYHQLYEYDV-UHFFFAOYSA-N 0.000 description 2
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 1
- 229910052493 LiFePO4 Inorganic materials 0.000 description 1
- 229910021312 NaFePO4 Inorganic materials 0.000 description 1
- 239000002033 PVDF binder Substances 0.000 description 1
- 238000007792 addition Methods 0.000 description 1
- 229910052783 alkali metal Inorganic materials 0.000 description 1
- 230000004888 barrier function Effects 0.000 description 1
- 239000002585 base Substances 0.000 description 1
- 230000008901 benefit Effects 0.000 description 1
- 125000001797 benzyl group Chemical group [H]C1=C([H])C([H])=C(C([H])=C1[H])C([H])([H])* 0.000 description 1
- 239000011230 binding agent Substances 0.000 description 1
- 239000012620 biological material Substances 0.000 description 1
- 230000005540 biological transmission Effects 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 230000000903 blocking effect Effects 0.000 description 1
- 210000000988 bone and bone Anatomy 0.000 description 1
- 229910052799 carbon Inorganic materials 0.000 description 1
- 239000006229 carbon black Substances 0.000 description 1
- 238000005266 casting Methods 0.000 description 1
- 150000001768 cations Chemical class 0.000 description 1
- 230000008859 change Effects 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 230000002860 competitive effect Effects 0.000 description 1
- 230000001010 compromised effect Effects 0.000 description 1
- 238000004590 computer program Methods 0.000 description 1
- 239000002482 conductive additive Substances 0.000 description 1
- 238000010276 construction Methods 0.000 description 1
- 230000001186 cumulative effect Effects 0.000 description 1
- 238000009792 diffusion process Methods 0.000 description 1
- 230000005611 electricity Effects 0.000 description 1
- 239000011267 electrode slurry Substances 0.000 description 1
- 239000004744 fabric Substances 0.000 description 1
- 230000002349 favourable effect Effects 0.000 description 1
- 239000002803 fossil fuel Substances 0.000 description 1
- 239000003517 fume Substances 0.000 description 1
- 239000005431 greenhouse gas Substances 0.000 description 1
- 238000003780 insertion Methods 0.000 description 1
- 230000037431 insertion Effects 0.000 description 1
- 230000003993 interaction Effects 0.000 description 1
- 150000002678 macrocyclic compounds Chemical class 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 210000003205 muscle Anatomy 0.000 description 1
- 239000010450 olivine Substances 0.000 description 1
- 229910052609 olivine Inorganic materials 0.000 description 1
- 210000000056 organ Anatomy 0.000 description 1
- 125000004430 oxygen atom Chemical group O* 0.000 description 1
- BASFCYQUMIYNBI-UHFFFAOYSA-N platinum Chemical compound [Pt] BASFCYQUMIYNBI-UHFFFAOYSA-N 0.000 description 1
- 239000004800 polyvinyl chloride Substances 0.000 description 1
- 229920002981 polyvinylidene fluoride Polymers 0.000 description 1
- 239000000843 powder Substances 0.000 description 1
- 238000010248 power generation Methods 0.000 description 1
- 150000003839 salts Chemical class 0.000 description 1
- 239000002002 slurry Substances 0.000 description 1
- 239000002904 solvent Substances 0.000 description 1
- 238000003860 storage Methods 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 125000001424 substituent group Chemical group 0.000 description 1
- 210000001519 tissue Anatomy 0.000 description 1
- 238000012546 transfer Methods 0.000 description 1
Images
Classifications
-
- C—CHEMISTRY; METALLURGY
- C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
- C25C—PROCESSES FOR THE ELECTROLYTIC PRODUCTION, RECOVERY OR REFINING OF METALS; APPARATUS THEREFOR
- C25C5/00—Electrolytic production, recovery or refining of metal powders or porous metal masses
- C25C5/02—Electrolytic production, recovery or refining of metal powders or porous metal masses from solutions
-
- C—CHEMISTRY; METALLURGY
- C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
- C25B—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES FOR THE PRODUCTION OF COMPOUNDS OR NON-METALS; APPARATUS THEREFOR
- C25B1/00—Electrolytic production of inorganic compounds or non-metals
- C25B1/01—Products
- C25B1/14—Alkali metal compounds
-
- C—CHEMISTRY; METALLURGY
- C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
- C25B—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES FOR THE PRODUCTION OF COMPOUNDS OR NON-METALS; APPARATUS THEREFOR
- C25B11/00—Electrodes; Manufacture thereof not otherwise provided for
- C25B11/02—Electrodes; Manufacture thereof not otherwise provided for characterised by shape or form
-
- C—CHEMISTRY; METALLURGY
- C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
- C25B—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES FOR THE PRODUCTION OF COMPOUNDS OR NON-METALS; APPARATUS THEREFOR
- C25B11/00—Electrodes; Manufacture thereof not otherwise provided for
- C25B11/04—Electrodes; Manufacture thereof not otherwise provided for characterised by the material
-
- C—CHEMISTRY; METALLURGY
- C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
- C25B—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES FOR THE PRODUCTION OF COMPOUNDS OR NON-METALS; APPARATUS THEREFOR
- C25B15/00—Operating or servicing cells
- C25B15/08—Supplying or removing reactants or electrolytes; Regeneration of electrolytes
- C25B15/083—Separating products
-
- C—CHEMISTRY; METALLURGY
- C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
- C25C—PROCESSES FOR THE ELECTROLYTIC PRODUCTION, RECOVERY OR REFINING OF METALS; APPARATUS THEREFOR
- C25C7/00—Constructional parts, or assemblies thereof, of cells; Servicing or operating of cells
- C25C7/02—Electrodes; Connections thereof
Definitions
- the present disclosure relates generally to systems and methods for concentrating ions. Particularly, embodiments of the present disclosure relate to electrochemical systems and methods for concentrating ions.
- Lithium is a strategically important resource, and a stable lithium supply is undoubtedly a key element to a sustainable future.
- civilization continues to develop, civilization continuously improves on the ability to harness energy.
- Civilization has progressed from animal power to steam power, and now civilization resides in the era of electrical power.
- today's electricity is largely obtained from fossil fuels that generate significant greenhouse gas emissions, creating a climate change risk. Due to the growing concern over this global challenge, it is desirable to create clean, zero-emission technologies for power generation. To achieve such a sustainable future, development in energy storage, generation, transmission, and usage will play a key role along the way.
- LIBs lithium-ion batteries
- the present disclosure relates generally to systems and methods for concentrating ions. Particularly, embodiments of the present disclosure relate to electrochemical systems and methods for concentrating ions.
- An exemplary embodiment of the present disclosure can provide a system for concentrating ions, the system comprising: an electrochemical cell comprising: a first electrode; a second electrode; a first solution in fluid communication with the first electrode and the second electrode, the first solution containing a first ion and a second ion, the second ion different from the first ion; and a molecular sieve disposed on the first electrode, the molecular sieve configured to selectively permit the first ion to pass from the solution to the first electrode.
- the molecular sieve can comprise a polymer.
- the molecular sieve can be further configured to selectively prevent the second ion from passing from the first solution to the first electrode.
- system can further comprise a voltage source configured to apply a differential voltage between the first electrode and the second electrode.
- the differential voltage can cause the electrochemical cell to undergo a redox reaction, wherein the redox reaction causes the first ion to absorb into the first electrode.
- the system can further comprise a second solution configured to, when contacted with the first electrode, desorb the first ion from the first electrode and into second solution.
- the first ion can be a lithium ion and the first electrode is a lithium-based electrode.
- the first solution can be a brine containing the first ion.
- Another embodiment of the present disclosure can provide a method of concentrating ions, comprising: contacting a first solution to an electrochemical cell, the first solution containing a first ion and a second ion, the second ion different than the first ion, the electrochemical cell comprising a first electrode, a second electrode, and a molecular sieve disposed on the first electrode, the molecular sieve configured to selectively permit the first ion to pass from the solution to the first electrode; applying a first differential voltage between the first electrode and the second electrode, wherein the first differential voltage causes the electrochemical cell to undergo a redox reaction such that the first ion absorb into the first electrode; contacting a second solution with the electrochemical cell; and applying a second differential voltage between the first electrode and the second electrode, wherein the second differential voltage causes the first ion to desorb from the first electrode.
- the molecular sieve can comprise a polymer.
- the molecular sieve can be further configured to selectively prevent the second ion from passing from the first solution to the first electrode.
- the first ion can be a lithium ion and the electrode is a lithium-based electrode.
- the first solution can be a brine containing the first ion.
- an electrochemical cell for concentrating ions comprising: a first electrode; a second electrode; a first solution in fluid communication with the first electrode and the second electrode, the first solution containing a first ion and a second ion, the second ion different than the first ion; and a molecular sieve disposed on the first electrode, the molecular sieve configured to selectively permit the first ion to pass from the solution to the first electrode.
- the molecular sieve can comprise a polymer.
- the molecular sieve can be further configured to selectively prevent the second ion from passing from the first solution to the first electrode.
- the electrode can be in electrical communication with a voltage source configured to apply a differential voltage between the first electrode and the second electrode.
- the differential voltage can cause a redox reaction, wherein the redox reaction causes the first ion to absorb into the first electrode.
- the first ion can be a lithium ion and the first electrode is a lithium-based electrode.
- the first solution can be a brine containing the first ion.
- FIG. 1 illustrates an example system for concentrating ions in accordance with the present disclosure.
- FIG. 2A illustrates an example molecular sieve in an electrochemical cell in accordance with the present disclosure.
- FIG. 2B illustrates an exploded view of the molecular sieve depicted in FIG. 2A in accordance with the present disclosure.
- FIG. 3 illustrates a flowchart of a method of concentrating ions in accordance with the present disclosure.
- FIG. 4 is a chart of the discharge curve for an electrode in various electrolytes in accordance with the present disclosure.
- FIG. 5A is a chart of the simulated steric energy of lithium ions in a molecular sieve in accordance with the present disclosure.
- FIG. 5B is a chart of the simulated steric energy of sodium ions in a molecular sieve in accordance with the present disclosure.
- FIG. 6 is a chart of electrochemical performance of an electrode and an electrode coated with a molecular sieve in accordance with the present disclosure.
- FIG. 7 is a chart of the molar ratio of lithium to sodium in different recovery solutions in accordance with the present disclosure.
- the world's oceans contain considerable amounts of lithium. In fact, the amount of lithium present in the world's oceans is around 16,000 times greater than the amount of land-based lithium. Additionally, extracting lithium from seawater would not be subjected to the geographic limitation of in-ground lithium sources. Although >99.9% of the world's lithium exists in the ocean, the dilute lithium ion concentration (varying around 0.1 to 0.2 ppm) greatly increases the difficulty of the recovery process. Moreover, the coexistence of other ions, such as sodium ions, having molar concentrations several orders of magnitude larger than the lithium ion concentration, adds an additional level of complication to any extraction process. Disclosed herein, therefore, are systems and methods to improve the extraction of lithium ions from seawater through an electrochemical process. The present disclosure can utilize the different electrochemical characteristics of lithium and sodium ions in saltwater.
- the disclosed technology can include an electrochemical cell for concentrating lithium ions.
- the electrochemical cell can have two electrodes and a solution therebetween allowing for ion and fluid flow between the two electrodes.
- the solution, saltwater in this example can contain many ions, such as lithium and sodium.
- a voltage can be applied to the electrochemical cell to initiate a redox reaction to force the lithium ions to one of the electrodes.
- the electrochemical cell can also include a molecular sieve disposed on one of the electrodes.
- the molecular sieve can be configured such that only lithium can pass through to reach the electrode, while preventing the other ions from passing through. In other words, the molecular sieve can aid in concentrating the lithium ions on the electrode while ensuring other ions remain in the solution.
- the electrochemical cell can be flushed with another solution and the redox reaction can be reversed to transfer the lithium ions from the electrode to the new solution. This new solution can be continually used to collect lithium ions until a desirable concentration is reached.
- tissue and “specimen” can refer to any plurality of biological cells, living or dead, and/or any number of other biomaterials, including, but not limited to, any single instance or plurality of bones, organs, muscles, and the like.
- FIG. 1 illustrates a system 100 for concentrating ions.
- the system 100 can comprise an electrochemical cell including a first electrode 110 , a second electrode 120 , and a first solution 130 in fluid communication with the first electrode 110 and the second electrode 120 .
- the first solution 130 can have a plurality of ions.
- the first solution 130 can have a first ion 132 (e.g., a target ion) and a second ion 134 (e.g., a non-target ion). It is understood that the first solution 130 can have multiple non-target ions, and that the first solution 130 can also have multiple target ions.
- the first ion 132 e.g., the target ion
- the second ion 134 e.g., the non-target ion
- any other ions remaining in the first solution 130 can be a non-target ion.
- the system 100 can also include a molecular sieve 210 disposed on the first electrode.
- the molecular sieve 210 is shown in greater detail in FIGS. 2A and 2B .
- the molecular sieve 210 can be configured to selectively permit the first ion 132 (e.g., the target ion) to pass through the molecular sieve 210 to move between the first solution 130 and the first electrode 110 .
- the molecular sieve 210 can also be configured to selectively prevent the second ion 134 (or any number of non-target ions) from passing from the first solution 130 to the first electrode 110 .
- the molecular sieve 210 can be any material that is nonreactive in the electrochemical cell that can create enough steric hinderance to non-target ions while allowing target ions to pass through.
- the molecular sieve 210 can be a polymer or polymeric material.
- the ions from the first solution can attempt to migrate to the first electrode 110 (or the second electrode 120 , depending on the polarity of the voltage).
- the first ion 132 can be the only ion to pass through the molecular sieve 210 to the first electrode 110 .
- the remaining ions can therefore be rejected by the molecular sieve 210 , remaining in the first solution 130 .
- the first ion 132 e.g., the target ion
- the first ion 132 can be concentrated at the first electrode 110 .
- the system 100 can further comprise a voltage source 140 that can apply a differential voltage between the first electrode 110 and the second electrode 120 .
- the voltage source 140 can be any device or component configured to create an electric potential, such as a battery, a power outlet, and the like.
- the differential voltage can cause the electrochemical cell to undergo a redox reaction.
- the redox reaction can cause the first ion 132 to absorb into the first electrode 110 .
- the system 100 can comprise a second solution 150 .
- the second solution can be brought into contact with the first electrode 110 such that the first ion 132 is desorbed from the first electrode 110 and into the second solution 150 . Because the redox reaction causes the first ion 132 to be absorbed into the first electrode 110 , and because the molecular sieve 210 prevents the second ion 134 (and other non-target ions) from reaching the first electrode, the second solution 150 can therefore become concentrated with the first ion 132 (e.g., the target ion).
- the second solution 150 can be removed from the system 100 to allow the first solution 130 to be added once again, thereby repeating the process.
- An example of such a process is described in greater detail below in FIG. 3 .
- FIG. 3 is described with respect to being performed by the system 100 , it is understood that the disclosure is not so limited. Indeed, some or all of the steps shown in FIG. 3 can be performed by other components of the system 100 or other similar systems.
- FIG. 3 is a flowchart of a method 300 of concentrating ions.
- the system 100 can contact the first solution 130 to the electrochemical cell.
- the first solution 130 can have a first ion 132 and a second ion 134 .
- the electrochemical cell can have a first electrode 110 , a second electrode 120 , and a molecular sieve 210 disposed on the first electrode 110 .
- the molecular sieve 210 can be configured to selectively permit the first ion 132 to pass from the first solution 130 to the first electrode 110 .
- the method 300 can then proceed on to block 320 .
- the system 100 can apply a first differential voltage to the electrochemical cell.
- the first differential voltage can be provided by the voltage source 140 .
- the first differential voltage can be applied between the first electrode 110 and the second electrode 120 , causing the electrochemical cell to undergo a redox reaction.
- the redox reaction can cause the first ion 132 to absorb into the first electrode 110 .
- the method 300 can then proceed on to block 330 .
- the system 100 can contact a second solution 150 with the electrochemical cell. This can be performed after the first solution 130 is flushed out of the electrochemical cell. Because the redox reaction causes the first ion 132 to be absorbed into the first electrode 110 , and because the molecular sieve 210 prevents the second ion 134 (and other non-target ions) from reaching the first electrode, the second solution 150 can therefore become concentrated with the first ion 132 . The method 300 can then proceed on to block 340 .
- the system can apply a second differential voltage to the electrochemical cell.
- the second differential voltage can be provided by the voltage source 140 , and the second differential voltage can be of opposite polarity to the first differential voltage.
- the second differential voltage can be applied between the first electrode 110 and the second electrode 120 , thereby causing the electrochemical cell to reverse the redox reaction cause by the first differential voltage.
- the first ion 132 can be desorbed from the first electrode 110 and into the second solution 150 .
- the method 300 can then terminate after block 340 .
- the second solution 150 can be removed from the system 100 to allow the first solution 130 to be added once again, thereby repeating the method 300 from block 310 .
- an electrochemical cell was build containing lithium iron phosphate (LFP) as the working electrode, platinum wire as a counter electrode, and a Ag/AgCL electrode as a reference electrode to test the electrochemical properties under various electrochemical environments.
- the cell was firstly discharged in pure lithium solution (0.1M LiCl), pure sodium solution (0.5M NaCl), or a mixture of lithium and sodium (0.1M LiCl+0.5M NaCl), which can artificially simulate the seawater condition where 0.5M NaCl is the nominal sodium concentration, to distinguish the potentials according to the intercalation of different ions.
- the intercalation of sodium onto the LFP can reduce the lithium storage capability because of the competitive relationship of the two ions.
- the olivine structure of the electrode can gradually transform to the thermodynamically preferable maricite structure induced by the insertion of sodium.
- the electrochemical reversibility of the LFP can be compromised, blocking the lithium diffusion channels.
- Crown ethers can be used to synthesize a lithium-selective polymer to act as an ion-sieve to allow lithium to pass but block sodium.
- lithium-selective ionophores can be used, and crown ethers can be used in particular due to their great capability to capture alkali metal cations thanks to the strong binding ability of the oxygen atoms. This can be based at least in part on the hard-soft and acid-base concept, without wishing to be bound by any one particular scientific theory.
- the ion-selectivity of crown ethers can be mostly based on the cavity size, where lithium can be mostly favorable to fit into the 14-member ring macrocycle (14-crown-4) from the examination of CPK space-filling models.
- Adding a benzyl group to the 14-crown-4, 6,6,-Dibenzyl-14-crown-4 can exhibit outstanding lithium selectivity, because introducing bulky substituents into the host ionophore can effectively suppress the formation of 2:1 or 3:1 sandwich-type ionophore-cation complexes with larger sized cations, such as sodium.
- the lithium ion-selective molecular sieve can contain 1.5% by weight of lithium ionophore VI (6,6,-Dibenzyl-14-crown-4), 0.5% by weight of potassium tetrakis(4-chlorophenyl)borate (KTCIPB), 28% by weight of polyvinylchloride (PVC), 68.5% by weight of 2-nitrophenyl octyl ether (NPOE), and 1.5% by weight of trioctylphosphine oxide (TOPO).
- the molecular sieve can be prepared by dissolving 100 mg of the mixture in 1 ml of tetrahydrofuran (THF) and stirred for 12 hours. The molecular sieve can then be prepared by casting the lithium-selective polymer on a polytetrafluoroethylene (PTFE) evaporating dish and placed in a fume hood for 24 hours to let the solvent fully evaporate.
- PTFE polytetrafluoroethylene
- the molecular sieve can be coated onto the LFP electrode and surface treated.
- the LFP powder can be mixed with a conductive additive (carbon black) and a binder (polyvinylidene fluoride) to prepare the electrode slurry.
- the slurry can be covered on carbon cloth to form the LFP electrode.
- the LFP electrode can be dipped into a molecular sieve solution to form the molecular sieve layer on the surface of the electrode.
- the surface treated LFP (STLFP) electrode can be formed.
- the electrode After forming the STLFP, the electrode can be placed in an electrochemical cell to test electrochemical performance.
- the electrode can be first placed in a cell full of artificial seawater and started to extract lithium.
- the discharge curve of STLFP does not show the plateau after ⁇ 0.15V, which corresponds to sodium intercalation.
- the single-plateau discharge curve of the STLFP can be attributed to the molecular sieve coating, indicating that the sodium intercalation can be greatly inhibited.
- the electrode Upon reaching the cutoff voltage ( ⁇ 0.2V), the electrode can be transferred to another cell, which can contain the recovery solution (0.1M KCl) to release the captured ions by charging.
- the recovery solution can be tested by ICP-ES to further confirm the effects of the molecular sieve coating. According to the ICP-ES measurements, the results can demonstrate the selectivity of the STLFP can be improved by a factor of 3.15.
- the molar ratio of lithium to sodium in the recovery solution can be 0.68 using the LFP and 2.15 using the STLFP, as shown in FIG. 7 .
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Electrochemistry (AREA)
- Materials Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Inorganic Chemistry (AREA)
- Water Treatment By Electricity Or Magnetism (AREA)
Abstract
Description
- This application claims the benefit of U.S. Provisional Application Ser. No. 62/949,763, filed on 18 Dec. 2019, the entire contents and substance of which is incorporated herein by reference in its entirety as if fully set forth below.
- The present disclosure relates generally to systems and methods for concentrating ions. Particularly, embodiments of the present disclosure relate to electrochemical systems and methods for concentrating ions.
- Lithium is a strategically important resource, and a stable lithium supply is undoubtedly a key element to a sustainable future. As civilization continues to develop, humanity continuously improves on the ability to harness energy. Civilization has progressed from animal power to steam power, and now civilization resides in the era of electrical power. However, today's electricity is largely obtained from fossil fuels that generate significant greenhouse gas emissions, creating a climate change risk. Due to the growing concern over this global challenge, it is desirable to create clean, zero-emission technologies for power generation. To achieve such a sustainable future, development in energy storage, generation, transmission, and usage will play a key role along the way.
- In the field of energy storage devices, lithium-ion batteries (LIBs) have become a focal point and dominant market force due to their preeminent performance. Recently, the prevalence of mobile devices, electric vehicles, internet of things devices, computation devices, and similar industries have led to an unprecedented demand for LIBs. For instance, the global electric vehicle cumulative sales are expected to rise from 2 million in 2016 to 1.8 billion by 2060. Additionally, the global demand for lithium is projected to quadruple from 2010 to 2025. That is to say, lithium is one of the most important resources for developing industries in the foreseeable future.
- However, current lithium production cannot meet the global demands of lithium. Currently, the majority of lithium production takes place in brine lakes and salt pans. Current methods, such as the lime-soda evaporation method, suffer from long manufacturing cycles and serious environmental impacts. These drawbacks lead to increased costs of energy storage and further hinder emerging technologies in energy storage. Therefore, the scarcity of lithium sources combined with inefficient methods of extracting said sources are a looming concern.
- What is needed, therefore, are systems and methods of lithium extraction that can more efficiently extract lithium from natural sources while minimizing the environmental impacts of such extraction processes. Embodiments of the present disclosure address this need as well as other needs that will become apparent upon reading the description below in conjunction with the drawings.
- The present disclosure relates generally to systems and methods for concentrating ions. Particularly, embodiments of the present disclosure relate to electrochemical systems and methods for concentrating ions.
- An exemplary embodiment of the present disclosure can provide a system for concentrating ions, the system comprising: an electrochemical cell comprising: a first electrode; a second electrode; a first solution in fluid communication with the first electrode and the second electrode, the first solution containing a first ion and a second ion, the second ion different from the first ion; and a molecular sieve disposed on the first electrode, the molecular sieve configured to selectively permit the first ion to pass from the solution to the first electrode.
- In any of the embodiments disclosed herein, the molecular sieve can comprise a polymer.
- In any of the embodiments disclosed herein, the molecular sieve can be further configured to selectively prevent the second ion from passing from the first solution to the first electrode.
- In any of the embodiments disclosed herein, the system can further comprise a voltage source configured to apply a differential voltage between the first electrode and the second electrode.
- In any of the embodiments disclosed herein, the differential voltage can cause the electrochemical cell to undergo a redox reaction, wherein the redox reaction causes the first ion to absorb into the first electrode.
- In any of the embodiments disclosed herein, the system can further comprise a second solution configured to, when contacted with the first electrode, desorb the first ion from the first electrode and into second solution.
- In any of the embodiments disclosed herein, the first ion can be a lithium ion and the first electrode is a lithium-based electrode.
- In any of the embodiments disclosed herein, the first solution can be a brine containing the first ion.
- Another embodiment of the present disclosure can provide a method of concentrating ions, comprising: contacting a first solution to an electrochemical cell, the first solution containing a first ion and a second ion, the second ion different than the first ion, the electrochemical cell comprising a first electrode, a second electrode, and a molecular sieve disposed on the first electrode, the molecular sieve configured to selectively permit the first ion to pass from the solution to the first electrode; applying a first differential voltage between the first electrode and the second electrode, wherein the first differential voltage causes the electrochemical cell to undergo a redox reaction such that the first ion absorb into the first electrode; contacting a second solution with the electrochemical cell; and applying a second differential voltage between the first electrode and the second electrode, wherein the second differential voltage causes the first ion to desorb from the first electrode.
- In any of the embodiments disclosed herein, the molecular sieve can comprise a polymer.
- In any of the embodiments disclosed herein, the molecular sieve can be further configured to selectively prevent the second ion from passing from the first solution to the first electrode.
- In any of the embodiments disclosed herein, the first ion can be a lithium ion and the electrode is a lithium-based electrode.
- In any of the embodiments disclosed herein, the first solution can be a brine containing the first ion.
- Another embodiment of the present disclosure can provide an electrochemical cell for concentrating ions, the electrochemical cell comprising: a first electrode; a second electrode; a first solution in fluid communication with the first electrode and the second electrode, the first solution containing a first ion and a second ion, the second ion different than the first ion; and a molecular sieve disposed on the first electrode, the molecular sieve configured to selectively permit the first ion to pass from the solution to the first electrode.
- In any of the embodiments disclosed herein, the molecular sieve can comprise a polymer.
- In any of the embodiments disclosed herein, the molecular sieve can be further configured to selectively prevent the second ion from passing from the first solution to the first electrode.
- In any of the embodiments disclosed herein, the electrode can be in electrical communication with a voltage source configured to apply a differential voltage between the first electrode and the second electrode.
- In any of the embodiments disclosed herein, the differential voltage can cause a redox reaction, wherein the redox reaction causes the first ion to absorb into the first electrode.
- In any of the embodiments disclosed herein, the first ion can be a lithium ion and the first electrode is a lithium-based electrode.
- In any of the embodiments disclosed herein, the first solution can be a brine containing the first ion.
- These and other aspects of the present disclosure are described in the Detailed Description below and the accompanying figures. Other aspects and features of embodiments of the present disclosure will become apparent to those of ordinary skill in the art upon reviewing the following description of specific, exemplary embodiments of the present invention in concert with the figures. While features of the present disclosure may be discussed relative to certain embodiments and figures, all embodiments of the present disclosure can include one or more of the features discussed herein. Further, while one or more embodiments may be discussed as having certain advantageous features, one or more of such features may also be used with the various embodiments of the invention discussed herein. In similar fashion, while exemplary embodiments may be discussed below as device, system, or method embodiments, it is to be understood that such exemplary embodiments can be implemented in various devices, systems, and methods of the present disclosure.
- The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate multiple embodiments of the presently disclosed subject matter and serve to explain the principles of the presently disclosed subject matter. The drawings are not intended to limit the scope of the presently disclosed subject matter in any manner.
-
FIG. 1 illustrates an example system for concentrating ions in accordance with the present disclosure. -
FIG. 2A illustrates an example molecular sieve in an electrochemical cell in accordance with the present disclosure. -
FIG. 2B illustrates an exploded view of the molecular sieve depicted inFIG. 2A in accordance with the present disclosure. -
FIG. 3 illustrates a flowchart of a method of concentrating ions in accordance with the present disclosure. -
FIG. 4 is a chart of the discharge curve for an electrode in various electrolytes in accordance with the present disclosure. -
FIG. 5A is a chart of the simulated steric energy of lithium ions in a molecular sieve in accordance with the present disclosure. -
FIG. 5B is a chart of the simulated steric energy of sodium ions in a molecular sieve in accordance with the present disclosure. -
FIG. 6 is a chart of electrochemical performance of an electrode and an electrode coated with a molecular sieve in accordance with the present disclosure. -
FIG. 7 is a chart of the molar ratio of lithium to sodium in different recovery solutions in accordance with the present disclosure. - As stated above, a problem with current lithium production processes is the scarcity of lithium. Furthermore, the processes to extract such scarce lithium have long manufacturing times, high energy inputs/costs, and harsh environmental impacts. Embodiments of the present disclosure address this need as well as other needs that will become apparent upon reading the description below in conjunction with the drawings.
- The world's oceans contain considerable amounts of lithium. In fact, the amount of lithium present in the world's oceans is around 16,000 times greater than the amount of land-based lithium. Additionally, extracting lithium from seawater would not be subjected to the geographic limitation of in-ground lithium sources. Although >99.9% of the world's lithium exists in the ocean, the dilute lithium ion concentration (varying around 0.1 to 0.2 ppm) greatly increases the difficulty of the recovery process. Moreover, the coexistence of other ions, such as sodium ions, having molar concentrations several orders of magnitude larger than the lithium ion concentration, adds an additional level of complication to any extraction process. Disclosed herein, therefore, are systems and methods to improve the extraction of lithium ions from seawater through an electrochemical process. The present disclosure can utilize the different electrochemical characteristics of lithium and sodium ions in saltwater.
- The disclosed technology can include an electrochemical cell for concentrating lithium ions. The electrochemical cell can have two electrodes and a solution therebetween allowing for ion and fluid flow between the two electrodes. The solution, saltwater in this example, can contain many ions, such as lithium and sodium. A voltage can be applied to the electrochemical cell to initiate a redox reaction to force the lithium ions to one of the electrodes. The electrochemical cell can also include a molecular sieve disposed on one of the electrodes. The molecular sieve can be configured such that only lithium can pass through to reach the electrode, while preventing the other ions from passing through. In other words, the molecular sieve can aid in concentrating the lithium ions on the electrode while ensuring other ions remain in the solution. Then, the electrochemical cell can be flushed with another solution and the redox reaction can be reversed to transfer the lithium ions from the electrode to the new solution. This new solution can be continually used to collect lithium ions until a desirable concentration is reached.
- Although certain embodiments of the disclosure are explained in detail, it is to be understood that other embodiments are contemplated. Accordingly, it is not intended that the disclosure is limited in its scope to the details of construction and arrangement of components set forth in the following description or illustrated in the drawings. Other embodiments of the disclosure are capable of being practiced or carried out in various ways. Also, in describing the embodiments, specific terminology will be resorted to for the sake of clarity. It is intended that each term contemplates its broadest meaning as understood by those skilled in the art and includes all technical equivalents which operate in a similar manner to accomplish a similar purpose.
- Herein, the use of terms such as “having,” “has,” “including,” or “includes” are open-ended and are intended to have the same meaning as terms such as “comprising” or “comprises” and not preclude the presence of other structure, material, or acts. Similarly, though the use of terms such as “can” or “may” are intended to be open-ended and to reflect that structure, material, or acts are not necessary, the failure to use such terms is not intended to reflect that structure, material, or acts are essential. To the extent that structure, material, or acts are presently considered to be essential, they are identified as such.
- By “comprising” or “containing” or “including” is meant that at least the named compound, element, particle, or method step is present in the composition or article or method, but does not exclude the presence of other compounds, materials, particles, method steps, even if the other such compounds, material, particles, method steps have the same function as what is named.
- It is also to be understood that the mention of one or more method steps does not preclude the presence of additional method steps or intervening method steps between those steps expressly identified.
- The components described hereinafter as making up various elements of the disclosure are intended to be illustrative and not restrictive. Many suitable components that would perform the same or similar functions as the components described herein are intended to be embraced within the scope of the disclosure. Such other components not described herein can include, but are not limited to, for example, similar components that are developed after development of the presently disclosed subject matter.
- As used herein, the terms “tissue” and “specimen” can refer to any plurality of biological cells, living or dead, and/or any number of other biomaterials, including, but not limited to, any single instance or plurality of bones, organs, muscles, and the like.
- Reference will now be made in detail to exemplary embodiments of the disclosed technology, examples of which are illustrated in the accompanying drawings and disclosed herein. Wherever convenient, the same references numbers will be used throughout the drawings to refer to the same or like parts.
-
FIG. 1 illustrates asystem 100 for concentrating ions. Thesystem 100 can comprise an electrochemical cell including afirst electrode 110, asecond electrode 120, and afirst solution 130 in fluid communication with thefirst electrode 110 and thesecond electrode 120. As shown, thefirst solution 130 can have a plurality of ions. In particular, thefirst solution 130 can have a first ion 132 (e.g., a target ion) and a second ion 134 (e.g., a non-target ion). It is understood that thefirst solution 130 can have multiple non-target ions, and that thefirst solution 130 can also have multiple target ions. For example, the first ion 132 (e.g., the target ion) can be lithium, and the second ion 134 (e.g., the non-target ion) can be sodium. In such an example, any other ions remaining in thefirst solution 130 can be a non-target ion. - The
system 100 can also include amolecular sieve 210 disposed on the first electrode. Themolecular sieve 210 is shown in greater detail inFIGS. 2A and 2B . Themolecular sieve 210 can be configured to selectively permit the first ion 132 (e.g., the target ion) to pass through themolecular sieve 210 to move between thefirst solution 130 and thefirst electrode 110. Themolecular sieve 210 can also be configured to selectively prevent the second ion 134 (or any number of non-target ions) from passing from thefirst solution 130 to thefirst electrode 110. Themolecular sieve 210 can be any material that is nonreactive in the electrochemical cell that can create enough steric hinderance to non-target ions while allowing target ions to pass through. For example, themolecular sieve 210 can be a polymer or polymeric material. - When a voltage is applied to the
system 100 to cause a redox reaction in the electrochemical cell, the ions from the first solution can attempt to migrate to the first electrode 110 (or thesecond electrode 120, depending on the polarity of the voltage). In such a manner, thefirst ion 132 can be the only ion to pass through themolecular sieve 210 to thefirst electrode 110. The remaining ions can therefore be rejected by themolecular sieve 210, remaining in thefirst solution 130. In such a manner, the first ion 132 (e.g., the target ion) can be concentrated at thefirst electrode 110. - Referring again to
FIG. 1 , thesystem 100 can further comprise avoltage source 140 that can apply a differential voltage between thefirst electrode 110 and thesecond electrode 120. Thevoltage source 140 can be any device or component configured to create an electric potential, such as a battery, a power outlet, and the like. As described above, the differential voltage can cause the electrochemical cell to undergo a redox reaction. The redox reaction can cause thefirst ion 132 to absorb into thefirst electrode 110. - Furthermore, the
system 100 can comprise asecond solution 150. The second solution can be brought into contact with thefirst electrode 110 such that thefirst ion 132 is desorbed from thefirst electrode 110 and into thesecond solution 150. Because the redox reaction causes thefirst ion 132 to be absorbed into thefirst electrode 110, and because themolecular sieve 210 prevents the second ion 134 (and other non-target ions) from reaching the first electrode, thesecond solution 150 can therefore become concentrated with the first ion 132 (e.g., the target ion). In some examples, once thefirst ion 132 is desorbed from thefirst electrode 110 and into thesecond solution 150, thesecond solution 150 can be removed from thesystem 100 to allow thefirst solution 130 to be added once again, thereby repeating the process. An example of such a process is described in greater detail below inFIG. 3 . - Although
FIG. 3 is described with respect to being performed by thesystem 100, it is understood that the disclosure is not so limited. Indeed, some or all of the steps shown inFIG. 3 can be performed by other components of thesystem 100 or other similar systems. -
FIG. 3 is a flowchart of amethod 300 of concentrating ions. As shown, inblock 310, thesystem 100 can contact thefirst solution 130 to the electrochemical cell. As described above, thefirst solution 130 can have afirst ion 132 and asecond ion 134. The electrochemical cell can have afirst electrode 110, asecond electrode 120, and amolecular sieve 210 disposed on thefirst electrode 110. Themolecular sieve 210 can be configured to selectively permit thefirst ion 132 to pass from thefirst solution 130 to thefirst electrode 110. Themethod 300 can then proceed on to block 320. - In
block 320, thesystem 100 can apply a first differential voltage to the electrochemical cell. The first differential voltage can be provided by thevoltage source 140. The first differential voltage can be applied between thefirst electrode 110 and thesecond electrode 120, causing the electrochemical cell to undergo a redox reaction. The redox reaction can cause thefirst ion 132 to absorb into thefirst electrode 110. Themethod 300 can then proceed on to block 330. - In
block 330, thesystem 100 can contact asecond solution 150 with the electrochemical cell. This can be performed after thefirst solution 130 is flushed out of the electrochemical cell. Because the redox reaction causes thefirst ion 132 to be absorbed into thefirst electrode 110, and because themolecular sieve 210 prevents the second ion 134 (and other non-target ions) from reaching the first electrode, thesecond solution 150 can therefore become concentrated with thefirst ion 132. Themethod 300 can then proceed on to block 340. - In
block 340, the system can apply a second differential voltage to the electrochemical cell. The second differential voltage can be provided by thevoltage source 140, and the second differential voltage can be of opposite polarity to the first differential voltage. The second differential voltage can be applied between thefirst electrode 110 and thesecond electrode 120, thereby causing the electrochemical cell to reverse the redox reaction cause by the first differential voltage. In such a manner, thefirst ion 132 can be desorbed from thefirst electrode 110 and into thesecond solution 150. Themethod 300 can then terminate afterblock 340. In some examples, however, once thefirst ion 132 is desorbed from thefirst electrode 110 and into thesecond solution 150, thesecond solution 150 can be removed from thesystem 100 to allow thefirst solution 130 to be added once again, thereby repeating themethod 300 fromblock 310. - Certain embodiments and implementations of the disclosed technology are described above with reference to block and flow diagrams of systems and methods and/or computer program products according to example embodiments or implementations of the disclosed technology. It will be understood that one or more blocks of the block diagrams and flow diagrams, and combinations of blocks in the block diagrams and flow diagrams, respectively, can be implemented by computer-executable program instructions. Likewise, some blocks of the block diagrams and flow diagrams may not necessarily need to be performed in the order presented, may be repeated, or may not necessarily need to be performed at all, according to some embodiments or implementations of the disclosed technology.
- While the present disclosure has been described in connection with a plurality of exemplary aspects, as illustrated in the various figures and discussed above, it is understood that other similar aspects can be used, or modifications and additions can be made to the described aspects for performing the same function of the present disclosure without deviating therefrom. For example, in various aspects of the disclosure, methods and compositions were described according to aspects of the presently disclosed subject matter. However, other equivalent methods or composition to these described aspects are also contemplated by the teachings herein. Therefore, the present disclosure should not be limited to any single aspect, but rather construed in breadth and scope in accordance with the appended claims.
- To better understand the interaction between lithium ions and sodium ions in seawater, an electrochemical cell was build containing lithium iron phosphate (LFP) as the working electrode, platinum wire as a counter electrode, and a Ag/AgCL electrode as a reference electrode to test the electrochemical properties under various electrochemical environments. The cell was firstly discharged in pure lithium solution (0.1M LiCl), pure sodium solution (0.5M NaCl), or a mixture of lithium and sodium (0.1M LiCl+0.5M NaCl), which can artificially simulate the seawater condition where 0.5M NaCl is the nominal sodium concentration, to distinguish the potentials according to the intercalation of different ions.
- As shown in
FIG. 4 , the difference in the discharge curve among the three different solutions can be clearly seen. In the lithium solution, the flat plateau at 0.05V can correspond to lithium intercalation. In the sodium solution, the tail below −0.15V can correspond to the sodium intercalation. However, two plateaus can be observed in the artificial seawater solution, indicating the co-intercalation of both ions onto the LFP. The reactions of the LFP electrode during discharge in the different electrolytes are shown inEquations -
In 0.1M LiCl solution: FePO4+Li+ +e −→LiFePO4 (1) -
In 0.5M NaCl solution: FePO4+Na+ +e −→NaFePO4 (2) -
In artificial seawater: FePO4 +xLi++(1−x)Na+ +e −→LixNa1−xFePO4 (3) - The intercalation of sodium onto the LFP can reduce the lithium storage capability because of the competitive relationship of the two ions. Moreover, the olivine structure of the electrode can gradually transform to the thermodynamically preferable maricite structure induced by the insertion of sodium. Thus, the electrochemical reversibility of the LFP can be compromised, blocking the lithium diffusion channels.
- Crown ethers can be used to synthesize a lithium-selective polymer to act as an ion-sieve to allow lithium to pass but block sodium. Several types of lithium-selective ionophores can be used, and crown ethers can be used in particular due to their great capability to capture alkali metal cations thanks to the strong binding ability of the oxygen atoms. This can be based at least in part on the hard-soft and acid-base concept, without wishing to be bound by any one particular scientific theory. The ion-selectivity of crown ethers can be mostly based on the cavity size, where lithium can be mostly favorable to fit into the 14-member ring macrocycle (14-crown-4) from the examination of CPK space-filling models. Adding a benzyl group to the 14-crown-4, 6,6,-Dibenzyl-14-crown-4 can exhibit outstanding lithium selectivity, because introducing bulky substituents into the host ionophore can effectively suppress the formation of 2:1 or 3:1 sandwich-type ionophore-cation complexes with larger sized cations, such as sodium.
- The lithium ion-selective molecular sieve can contain 1.5% by weight of lithium ionophore VI (6,6,-Dibenzyl-14-crown-4), 0.5% by weight of potassium tetrakis(4-chlorophenyl)borate (KTCIPB), 28% by weight of polyvinylchloride (PVC), 68.5% by weight of 2-nitrophenyl octyl ether (NPOE), and 1.5% by weight of trioctylphosphine oxide (TOPO). The molecular sieve can be prepared by dissolving 100 mg of the mixture in 1 ml of tetrahydrofuran (THF) and stirred for 12 hours. The molecular sieve can then be prepared by casting the lithium-selective polymer on a polytetrafluoroethylene (PTFE) evaporating dish and placed in a fume hood for 24 hours to let the solvent fully evaporate.
- To further understand the effect of the molecular sieve, a simulation of the steric energy of the intermediate states of the 6,6-Dibenzyl-14-crown-4 binding with lithium and sodium were performed. As shown in
FIGS. 5A and 5B , respectively, each simulation run had the test ions of the same species set at both sides of the crown ether to be converged to the lowest energy point (stable point). The lithium spontaneously can pass through the cavity of the crown ether from the right to the left to reach the stable point. However, the sodium ion is blocked by the cavity from both sides due to the high energy barrier that occurs when sodium is in the center of the cavity. In such a manner, the simulations can demonstrate the efficacy of the molecular sieve toward a high selectivity of lithium over sodium. - To further dispose the molecular sieve onto the electrode, the molecular sieve can be coated onto the LFP electrode and surface treated. First, the LFP powder can be mixed with a conductive additive (carbon black) and a binder (polyvinylidene fluoride) to prepare the electrode slurry. Then, the slurry can be covered on carbon cloth to form the LFP electrode. Subsequently, the LFP electrode can be dipped into a molecular sieve solution to form the molecular sieve layer on the surface of the electrode. In such a manner, the surface treated LFP (STLFP) electrode can be formed.
- After forming the STLFP, the electrode can be placed in an electrochemical cell to test electrochemical performance. The electrode can be first placed in a cell full of artificial seawater and started to extract lithium. As shown in
FIG. 6 , unlike LFP, the discharge curve of STLFP does not show the plateau after −0.15V, which corresponds to sodium intercalation. The single-plateau discharge curve of the STLFP can be attributed to the molecular sieve coating, indicating that the sodium intercalation can be greatly inhibited. Upon reaching the cutoff voltage (−0.2V), the electrode can be transferred to another cell, which can contain the recovery solution (0.1M KCl) to release the captured ions by charging. - The recovery solution can be tested by ICP-ES to further confirm the effects of the molecular sieve coating. According to the ICP-ES measurements, the results can demonstrate the selectivity of the STLFP can be improved by a factor of 3.15. The molar ratio of lithium to sodium in the recovery solution can be 0.68 using the LFP and 2.15 using the STLFP, as shown in
FIG. 7 .
Claims (20)
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US17/126,652 US20210189578A1 (en) | 2019-12-18 | 2020-12-18 | Systems and Methods for Concentrating Ions |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US201962949763P | 2019-12-18 | 2019-12-18 | |
US17/126,652 US20210189578A1 (en) | 2019-12-18 | 2020-12-18 | Systems and Methods for Concentrating Ions |
Publications (1)
Publication Number | Publication Date |
---|---|
US20210189578A1 true US20210189578A1 (en) | 2021-06-24 |
Family
ID=76437904
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US17/126,652 Pending US20210189578A1 (en) | 2019-12-18 | 2020-12-18 | Systems and Methods for Concentrating Ions |
Country Status (1)
Country | Link |
---|---|
US (1) | US20210189578A1 (en) |
Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20090218237A1 (en) * | 2006-04-24 | 2009-09-03 | Martial Berger | Lithium ion-selective membrane |
US20100323247A1 (en) * | 2008-02-06 | 2010-12-23 | Sony Corporation | Electrolyte and battery |
US20120082893A1 (en) * | 2010-10-01 | 2012-04-05 | GM Global Technology Operations LLC | Lithium ion battery |
US20150004473A1 (en) * | 2013-07-01 | 2015-01-01 | Samsung Sdi Co., Ltd. | Secondary battery |
US20180246054A1 (en) * | 2015-09-14 | 2018-08-30 | Hitachi High-Technologies Corporation | Ion-Selective Electrode, Method of Manufacture Thereof, and Cartridge |
-
2020
- 2020-12-18 US US17/126,652 patent/US20210189578A1/en active Pending
Patent Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20090218237A1 (en) * | 2006-04-24 | 2009-09-03 | Martial Berger | Lithium ion-selective membrane |
US20100323247A1 (en) * | 2008-02-06 | 2010-12-23 | Sony Corporation | Electrolyte and battery |
US20120082893A1 (en) * | 2010-10-01 | 2012-04-05 | GM Global Technology Operations LLC | Lithium ion battery |
US20150004473A1 (en) * | 2013-07-01 | 2015-01-01 | Samsung Sdi Co., Ltd. | Secondary battery |
US20180246054A1 (en) * | 2015-09-14 | 2018-08-30 | Hitachi High-Technologies Corporation | Ion-Selective Electrode, Method of Manufacture Thereof, and Cartridge |
Non-Patent Citations (1)
Title |
---|
Xie et al. Lithium Ion-selective Electrodes Containing TOPO: Determination of Serum Lithium by Flow Injection Analysis. Analyst, January 1987, Vol. 112. Pages 61-64. (Year: 1987) * |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
Huang et al. | Novel insights into energy storage mechanism of aqueous rechargeable Zn/MnO 2 batteries with participation of Mn 2+ | |
Zhou et al. | Boosting the electrochemical performance through proton transfer for the Zn-ion hybrid supercapacitor with both ionic liquid and organic electrolytes | |
He et al. | New insights into the application of lithium‐ion battery materials: selective extraction of lithium from brines via a rocking‐chair lithium‐ion battery system | |
Soto et al. | Tuning the solid electrolyte interphase for selective Li‐and Na‐ion storage in hard carbon | |
Lee et al. | Highly selective lithium recovery from brine using a λ-MnO 2–Ag battery | |
Wu et al. | In situ formation of stable interfacial coating for high performance lithium metal anodes | |
Song et al. | Aqueous Sodium‐Ion Battery using a Na3V2 (PO4) 3 Electrode | |
Marchini et al. | Surface chemistry and lithium-ion exchange in LiMn2O4 for the electrochemical selective extraction of LiCl from natural salt lake brines | |
Ling et al. | Thermodynamic origin of irreversible magnesium trapping in chevrel phase Mo6S8: importance of magnesium and vacancy ordering | |
CN103972584B (en) | electrolyte carrier film, electrolyte and preparation method thereof and lithium ion battery | |
JP5756068B2 (en) | Sodium secondary battery | |
CN107154486A (en) | A kind of cupric multi-element metal sulfide is the sodium-ion battery of negative material | |
CN103545120B (en) | Rice husk matrix activated carbon is as the organic system mixed capacitor of electrode material | |
CN105261742A (en) | Chalcogenide semi-solid lithium battery and preparing method thereof | |
CN106252641B (en) | Ternary cathode material of lithium ion battery and preparation method are covered in carbon and ceria double-contracting | |
Zhang et al. | A nanocellulose-mediated, multiscale ion-sieving separator with selective Zn2+ channels for durable aqueous zinc-based batteries | |
Ponnada et al. | Improved performance of lithium–sulfur batteries by employing a sulfonated carbon nanoparticle-modified glass fiber separator | |
CN108172406A (en) | One kind is with FeS2-xSexMaterial is the sodium ion capacitor of negative material | |
Van Pham et al. | Stabilization of Li–S batteries with a lean electrolyte via ion-exchange trapping of lithium polysulfides using a cationic, polybenzimidazolium binder | |
CN109346770A (en) | A kind of electrolyte and the lithium-sulfur cell and its preparation method and application using it | |
Xu et al. | Selective pseudocapacitive separation of zinc ions via silk cocoon derived N-doped porous carbon | |
Jiménez | The counter electrode in electrochemical lithium recovery | |
Rethinasabapathy et al. | Efficient lithium extraction using redox-active Prussian blue nanoparticles-anchored activated carbon intercalation electrodes via membrane capacitive deionization | |
Kreissl et al. | Electrochemical lithiation/delithiation of ZnO in 3D-structured electrodes: elucidating the mechanism and the solid electrolyte interphase formation | |
Wang et al. | Unraveling the high Energy efficiency for Zn|| metal hexacyanoferrate batteries in a zinc-potassium hybrid configuration |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
AS | Assignment |
Owner name: GEORGIA TECH RESEARCH CORPORATION, GEORGIA Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:LIU, NIAN;HUANG, PO-WEI;REEL/FRAME:054740/0719 Effective date: 20201221 |
|
STPP | Information on status: patent application and granting procedure in general |
Free format text: APPLICATION DISPATCHED FROM PREEXAM, NOT YET DOCKETED |
|
STPP | Information on status: patent application and granting procedure in general |
Free format text: DOCKETED NEW CASE - READY FOR EXAMINATION |
|
STPP | Information on status: patent application and granting procedure in general |
Free format text: NON FINAL ACTION MAILED |
|
STPP | Information on status: patent application and granting procedure in general |
Free format text: RESPONSE TO NON-FINAL OFFICE ACTION ENTERED AND FORWARDED TO EXAMINER |
|
STPP | Information on status: patent application and granting procedure in general |
Free format text: NON FINAL ACTION MAILED |
|
STPP | Information on status: patent application and granting procedure in general |
Free format text: RESPONSE TO NON-FINAL OFFICE ACTION ENTERED AND FORWARDED TO EXAMINER |
|
STPP | Information on status: patent application and granting procedure in general |
Free format text: FINAL REJECTION MAILED |
|
STPP | Information on status: patent application and granting procedure in general |
Free format text: DOCKETED NEW CASE - READY FOR EXAMINATION |
|
STPP | Information on status: patent application and granting procedure in general |
Free format text: NON FINAL ACTION MAILED |