Materials derived from coal using environmentally friendly solvents

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.

What is claimed is: 
     
         1 . A coal treatment process, comprising:
 exposing a material comprising coal to one or more ionic liquids 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.   
     
     
         2 . The process 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 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 ). 
 
     
     
         3 . The process of  claim 1 , wherein the ionic liquid is represented by one or more of 
       
         
           
           
               
               
           
         
       
     
     
         4 . The process of  claim 1 , further comprising:
 selecting the ionic liquid based on a zeta potential of a composition comprising an ionic liquid adsorbed on coal.   
     
     
         5 . The process of  claim 1 , further comprising:
 adding a precursor, binder, or a combination thereof to the residue to form a second mixture.   
     
     
         6 . The process of  claim 5 , wherein the precursor, binder, or a combination thereof is polyvinylpyrrolidone (PVP), polyacrylonitrile (PAN), poly(acrylonitrile-co-methyl acrylate) (PANMA), poly(methyl methacrylate) (PMMA), polyimide (PI), polyvinylidene fluoride (PVDF), polyvinyl alcohol (PVA), and polystyrene (PS). 
     
     
         7 . The process of  claim 5 , further comprising:
 exposing the carbon fiber precursor material to an ambient air environment at a temperature between about 250° C. and about 350° C.   
     
     
         8 . The process of  claim 5 , further comprising:
 carbonizing the carbon fiber precursor material at a temperature between about 800° C. and about 1000° C.; and   forming a carbon fiber material.   
     
     
         9 . The process of  claim 8 , wherein the carbon fiber material has:
 a capacitance of more than about 160 F/g; and   a conductivity of more than about 1 S/cm.   
     
     
         10 . A coal treatment process comprising:
 exposing a material comprising coal to one or more ionic liquids 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.   
     
     
         11 . The process of  claim 10 , wherein the separating and filtering comprises performing solid phase extraction. 
     
     
         12 . The process of  claim 10 , 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 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), 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 ). 
 
     
     
         13 . The process of  claim 10 , wherein the ionic liquid is represented by one or more of 
       
         
           
           
               
               
           
         
       
     
     
         14 . The process of  claim 10 , wherein the ionic liquid is 
       
         
           
           
               
               
           
         
       
     
     
         15 . The process of  claim 10 , further comprising:
 selecting the ionic liquid based on a zeta potential of a composition comprising an ionic liquid adsorbed on coal.   
     
     
         16 . The process of  claim 10 , wherein the compounds are selected from the group consisting of fatty acids, ethoxy diols, quinones, and amines. 
     
     
         17 . A coal treatment process, comprising:
 exposing a material comprising coal to one or more ionic liquids 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.   
     
     
         18 . The process of  claim 18 , further comprising:
 performing a membrane solvent exchange; and   performing one or more of precipitation, drying, and annealing.   
     
     
         19 . The process of  claim 18 , 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 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 ). 
 
     
     
         20 . The process of  claim 19 , wherein the ionic liquid is represented by one or more of