Materials derived from coal using environmentally friendly solvents

Patent metadata

Field	Value
Publication number	US-11761058-B2
Application number	US-202217864857-A
Country	US
Kind code	B2
Filing date	Jul 14, 2022
Priority date	Jan 5, 2017
Publication date	Sep 19, 2023
Grant date	Sep 19, 2023

Abstract

In a first embodiment, a coal treatment process includes exposing a material comprising coal to ionic liquid(s) to form a first mixture, isolating a residue from the first mixture, forming a second mixture comprising the residue, and electrospinning the second mixture to form a carbon fiber precursor material. In a second embodiment, a coal treatment process includes exposing a material comprising coal to ionic liquid(s) to form a mixture comprising solids and a liquid fraction, separating and filtering the liquid fraction from the mixture, and isolating one or more compounds from the liquid fraction. In a third embodiment, a coal treatment process includes exposing a material comprising coal to ionic liquid(s) to form a first mixture comprising residues, exposing the first mixture to (a) an acid, (b) a solvent, or (c) both to form a second mixture, and isolating rare earth elements and rare earth element compounds.

First claim

What is claimed is:

1. A coal treatment method, comprising:
exposing coal or coal byproducts to an ionic liquid to form residues and a liquid fraction; and
isolating rare earth elements from the residues by treating the residues with an acid, wherein the isolating rare earth elements further comprises:
performing a membrane solvent exchange on the residues and the acid to recover an extract comprising the rare earth elements.

2. The method of claim 1 , further comprising precipitating the rare earth elements from the extract.

3. The method of claim 1 , wherein at least a portion of the rare earth elements are in the form of oxides.

4. A coal treatment method, comprising:
exposing coal or coal byproducts to an ionic liquid to form residues and a liquid fraction;
isolating rare earth elements from the residues by treating the residues with an acid;
removing the liquid fraction prior to treating the residues with the acid; and
recovering organic compounds by performing solid-phase extraction on the liquid fraction.

5. The method of claim 1 , wherein the ionic liquid is represented by formula (A) or formula (B):

wherein:
each of R 1 and R 3 is independently a hydrocarbyl radical or a substituted hydrocarbyl radical;
each of R 2 , R 4 , and R 5 is independently a hydrogen, a hydrocarbyl radical, a substituted hydrocarbyl radical, a C 4 to C 20 aryl radical, or a substituted C 4 to C 20 aryl radical;
each of R 6 , R 7 , R 8 , and R 9 is independently a hydrogen, a hydrocarbyl radical, a substituted hydrocarbyl radical, a C 4 to C 20 aryl radical, or a substituted C 4 to C 20 aryl radical, or two or more adjacent R 6 , R 7 , R 8 , and R 9 groups are independently joined together to form a substituted or unsubstituted hydrocarbyl ring or heterocyclic ring, where the substituted or unsubstituted hydrocarbyl ring or heterocyclic ring has 5, 6, 7, or 8 ring atoms; and
X is independently chloride (Cl), bromide (Br), iodide (I), thiocyanate (SCN), hexafluorophosphate (PF 6 ), antimony hexafluoride (SbF 6 ), bis(trifluoromethyl-sulfonyl)imide (NTf 2 ), tetrafluoroborate (BF 4 ), tetracyanoborate (B(CN) 4 ), trifluoromethanesulfonate (OTf), dicyanamide (N(CN) 2 ), alkyl sulfate (C n H 2n+1 OSO 3 , where n=0, 1, or 8, such as methyl sulfate), dimethyl phosphate (Me 2 PO 4 ), or acetate (MeCO 2 ).

6. The method of claim 5 , wherein:
each of R 1 and R 3 is independently a C 1 to C 20 hydrocarbyl radical; and
both R 4 and R 5 are hydrogen.

7. The method of claim 6 , wherein R 2 is hydrogen or methyl.

8. The method of claim 5 , wherein the ionic liquid is one or more of

9. The method of claim 1 , wherein the acid comprises nitric acid or sulfuric acid.

10. The method of claim 1 , wherein:
the coal or the coal byproducts is coal ash; and
the acid is nitric acid.

11. A coal treatment method, comprising:
selecting an ionic liquid based on a zeta potential of a composition comprising the ionic liquid adsorbed on coal;
forming a first mixture comprising coal ash and the ionic liquid, the ionic liquid having the formula

wherein:
each of R 1 and R 3 is independently a hydrocarbyl radical or a substituted hydrocarbyl radical;
each of R 2 , R 4 , and R 5 is independently a hydrogen, a hydrocarbyl radical, a substituted hydrocarbyl radical, a C 4 to C 20 aryl radical, or a substituted C 4 to C 20 aryl radical; and
X is independently chloride (Cl), bromide (Br), iodide (I), thiocyanate (SCN), hexafluorophosphate (PF 6 ), antimony hexafluoride (SbF 6 ), bis(trifluoromethyl-sulfonyl)imide (NTf 2 ), tetrafluoroborate (BF 4 ), tetracyanoborate (B(CN) 4 ), trifluoromethanesulfonate (OTf), dicyanamide (N(CN) 2 ), alkyl sulfate (C n H 2n+1 OSO 3 , where n=0, 1, or 8, such as methyl sulfate), dimethyl phosphate (Me 2 PO 4 ), or acetate (MeCO 2 );

exposing the first mixture to an acid and a solvent to form a second mixture; and
isolating rare earth elements or rare earth element oxides from the second mixture.

12. The method of claim 11 , wherein the isolating rare earth elements or rare earth element oxides from the second mixture comprises:
performing a membrane solvent exchange on the second mixture to recover an extract; and
removing the rare earth elements or the rare earth element oxides from the extract by precipitating, drying, or annealing.

13. The method of claim 11 , wherein the solvent comprises N-methyl-2-pyrrolidone, trifluoroacetic acid, trichloroacetic acid, dichloromethane, dimethylsulfoxide, or combinations thereof.

14. The method of claim 11 , wherein the acid comprises nitric acid or sulfuric acid.

15. The method of claim 11 , wherein:
each of R 1 and R 3 is independently a C 1 to C 20 hydrocarbyl radical; and
both R 4 and R 5 are hydrogen.

16. The method of claim 11 , wherein the ionic liquid comprises one or more of

17. The method of claim 11 , wherein the ionic liquid comprises one or more of

18. A coal treatment method, comprising:
exposing coal to an ionic liquid to obtain a residue, the ionic liquid having the formula

wherein:
each of R 1 and R 3 is independently a C 1 to C 20 hydrocarbyl radical;
R 2 is hydrogen or methyl;
both R 4 and R 5 are hydrogen; and
X is chloride (Cl), bromide (Br), iodide (I), hexafluorophosphate (PF 6 ), antimony hexafluoride (SbF 6 ), bis(trifluoromethyl-sulfonyl)imide (NTf 2 ), tetrafluoroborate (BF 4 );

exposing the residue to acid and a solvent to form a mixture, the acid comprising nitric acid or sulfuric acid;
performing a membrane solvent exchange on the mixture to form an extract; and
precipitating, drying, or annealing the extract to obtain rare earth element oxides.

19. The method of claim 18 , wherein:
the coal comprises coal ash;
the acid comprises nitric acid; and
the ionic liquid comprises one or more of

20. The method of claim 4 , wherein at least a portion of the rare earth elements are in the form of oxides.

21. The method of claim 4 , wherein the ionic liquid is represented by formula (A) or formula (B):

wherein:
each of R 1 and R 3 is independently a hydrocarbyl radical or a substituted hydrocarbyl radical;
each of R 2 , R 4 , and R 5 is independently a hydrogen, a hydrocarbyl radical, a substituted hydrocarbyl radical, a C 4 to C 20 aryl radical, or a substituted C 4 to C 20 aryl radical;
each of R 6 , R 7 , R 8 , and R 9 is independently a hydrogen, a hydrocarbyl radical, a substituted hydrocarbyl radical, a C 4 to C 20 aryl radical, or a substituted C 4 to C 20 aryl radical, or two or more adjacent R 6 , R 7 , R 8 ,

Assignees

• Univ Wyoming

Inventors

• Li Dongmei
• Tan Shuai
• Li Chenlin
• Williams Luke

Classifications

• C22B59/00 Primary

  Obtaining rare earth metals · CPC title

• D01F1/02

  Addition of substances to the spinning solution or to the melt (addition of substances to viscose D01F2/08) · CPC title

• D01F9/14

  by decomposition of organic filaments · CPC title

• C22B3/22

  by physical processes, e.g. by filtration, by magnetic means {, or by thermal decomposition} (treatment or purification of solutions by liquid-liquid extraction C22B3/26) · CPC title

• D01F9/22

  from polyacrylonitriles · CPC title