Methods of forming metals using ionic liquids

Patent metadata

Field	Value
Publication number	US-2019186031-A1
Application number	US-201715847757-A
Country	US
Kind code	A1
Filing date	Dec 19, 2017
Priority date	Dec 19, 2017
Publication date	Jun 20, 2019
Grant date	—

Abstract

A method of forming an elemental metal (e.g., a rare-earth element) includes forming a multicomponent solution comprising an ionic liquid, a secondary component, and a metal-containing compound. The multicomponent solution is contacted with at least a first electrode and a second electrode. A current is passed between the first electrode to the second electrode through the multicomponent solution. The metal-containing compound is reduced to deposit the elemental metal therefrom on the first electrode.

First claim

What is claimed is:

1 . A method of forming an elemental metal, the method comprising:
forming a multicomponent solution comprising an ionic liquid, a secondary component, and a metal-containing compound; contacting the multicomponent solution with at least a first electrode and a second electrode; passing a current between the first electrode to the second electrode through the multicomponent solution; and reducing the metal-containing compound to deposit metal therefrom on the first electrode.

2 . The method of claim 1 , wherein the secondary component comprises a material selected from the group consisting of a gas, a liquid, a salt, and a supercritical fluid.

3 . The method of claim 1 , wherein the secondary component comprises a second ionic liquid.

4 . The method of claim 1 , wherein forming a multicomponent solution comprises forming the multicomponent solution to comprise the ionic liquid, the secondary component, the metal-containing compound, and an anolyte.

5 . The method of claim 4 , wherein the anolyte comprises a material selected from the group consisting of formic acid, ammonia, oxalic acid, acetic acid, carboxylic acids, and phthalic acid.

6 . The method of claim 4 , further comprising oxidizing the anolyte at the second electrode.

7 . The method of claim 1 , wherein forming a multicomponent solution comprises dissolving the metal-containing compound in the ionic liquid.

8 . The method of claim 1 , wherein forming a multicomponent solution comprises dissolving the metal-containing compound in the multicomponent solution at a concentration higher than a solubility limit of the metal-containing compound in the ionic liquid alone.

9 . The method of claim 1 , wherein the metal-containing compound comprises a compound containing a rare-earth element, and wherein the metal deposited comprises the rare-earth element.

10 . The method of claim 1 , wherein the metal-containing compound comprises a metal species selected from the group consisting of a metal oxide, a metal nitrate, a metal triflate, a metal carbonate, a metal bistriflimide, a metal-ligand complex, and ionic-liquid-bound metal, and a dissolved metal.

11 . The method of claim 1 , wherein reducing the metal-containing compound to deposit metal therefrom on the first electrode comprises depositing the metal onto the first electrode at a temperature of less than 200° C.

12 . The method of claim 1 , wherein reducing the metal-containing compound to deposit metal therefrom on the first electrode comprises depositing the metal onto the first electrode at a temperature between 0° C. and 100° C.

13 . The method of claim 1 , wherein reducing the metal-containing compound to deposit metal therefrom on the first electrode comprises depositing at least one metal selected from the group consisting of Nd, Pr, Eu, Dy, Sm, Ho, Sc, Y, La, Ce, Pm, Gd, Tb, Er, Tm, Yb, and Lu onto the first electrode.

14 . The method of claim 1 , further comprising separating the multicomponent solution from the first electrode and the second electrode after reducing the metal-containing compound.

15 . The method of claim 14 , further comprising regenerating the ionic liquid after separating the multicomponent solution from the first electrode and the second electrode.

16 . The method of claim 15 , further comprising recycling the regenerated ionic liquid to form the multicomponent solution.

17 . The method of claim 1 , wherein reducing the metal-containing compound to deposit metal therefrom on the first electrode comprises depositing at least one metal selected from the group consisting of transition metals, actinides, and alloys and mixtures thereof onto the first electrode.

18 . A method of forming an elemental metal, the method comprising:
providing an anode and a cathode, each in contact with an ionic liquid, the ionic liquid comprising a dissolved species; providing a metal-containing compound within the ionic liquid; and passing a current through the anode and the cathode to reduce the metal-containing compound and deposit an elemental metal therefrom onto the cathode.

19 . The method of claim 18 , wherein the dissolved species comprises a material selected from the group consisting of a dissolved gas, a dissolved liquid, a dissolved salt, and a dissolved supercritical fluid.

20 . The method of claim 18 , wherein the dissolved species comprises another ionic liquid.

21 . The method of claim 18 , further comprising providing an anolyte in the ionic liquid and oxidizing the anolyte at the anode.

22 . The method of claim 18 , wherein passing a current through the anode and the cathode comprises depositing the metal onto the cathode at a temperature of less than 200° C.

23 . The method of claim 18 , wherein passing a current through the anode and the cathode comprises depositing the metal onto the cathode at a temperature between 0° C. and 100° C.

24 . The method of claim 18 , wherein providing a metal-containing compound within the ionic liquid comprises providing a metal species selected from the group consisting of a metal oxide, a metal nitrate, a metal triflate, a metal carbonate, a metal bistriflimide, a metal-ligand complex, and ionic-liquid-bound metal, and a dissolved metal.

25 . A method for forming solid metal, the method comprising:
continuously passing a current through a cathode, an ionic liquid, and an anode to reduce a metal-containing compound mixed with the ionic liquid and deposit an elemental metal therefrom onto the cathode, wherein the ionic liquid comprises a dissolved species in addition to the metal-containing compound.

26 . The method of claim 25 , further comprising continuously flowing the ionic liquid through a vessel containing the anode and the cathode.

27 . The method of claim 26 , further comprising continuously regenerating a portion of the ionic liquid leaving the vessel.

28 . The method of claim 27 , further comprising recycling the regenerated portion of the ionic liquid to the vessel.

29 . The method of claim 25 , wherein the dissolved species comprises a second ionic liquid.

30 . The method of claim 25 , wherein the ionic liquid comprises at least one material selected from the group consisting of N-ethyl-N-methylpyrrolidinium, N-methyl-N-propylpyrrolidinium, N-methyl-N-isopropylpyrrolidinium, N-butyl-N-methylpyrrolidinium, N-isobutyl-N-methylpyrrolidinium, N-secbutyl-N-methylpyrrolidinium, N-methyl-N-pentylpyrrolidinium, N-hexyl-N-methylpyrrolidinium, N-heptyl-N-methylpyrrolidinium, N-methyl-N-octylpyrrolidinium, N-methyl-N-propylpiperidinium, N-butyl-N-ethyl-piperidinium, N-ethyl-N-octylpiperidinium, N-trimethylbutylammonium, N-hexyltriethylammonium, tetrabutylammonium, trimethyl-N-hexylammonium, dimethylethylphenylammonium, triethylmethylammonium, trihexyl(tetradecyl)phosphonium, tetradecyl(trioctyl)phosphonium, triethyl-pentyl-phosphonium, triethyl-octyl-phosphonium, triethyl-dodecyl-phosphonium, bis(trifluoromethanesulfonyl)imide, trifluoromethanesulfonate, and dicyanimide.

31 . The method of claim 25 , wherein continuously passing a current through an anode, an ionic liquid, and a cathode comprises reducing a rare-earth metal from the metal-containing compound and depositing the rare-earth metal onto the cathode.

32 . A multicomponent s

Assignees

• Battelle Energy Alliance Llc

Inventors

• Baek Donna L
• Fox Robert V
• Lister Tedd E

Classifications

• C25C3/34 Primary

  of metals not provided for in groups C25C3/02 - C25C3/32 · CPC title

• C25C7/06

  Operating or servicing · CPC title