Ionic liquids as solvents in headspace gas chromatography

Abstract

A method of using an ionic liquid as solvent in headspace gas chromatography.

1 . A method of using ionic liquids as solvents in headspace gas chromatography wherein said method comprises dissolving or dispersing a sample in at least one ionic liquid, wherein the ionic liquid is a molten salt and volatilizing the volatile components of the sample. 
   
   
       2 . The method according to  claim 1  wherein the ionic liquid has a melting point of less than 100° C. 
   
   
       3 . The method according to  claim 2  wherein the ionic liquid has a melting point of less than 30° C. 
   
   
       4 . The method according to  claim 1  ionic liquid has a vapor pressure of less than about 1 mm/Hg at 25° C. 
   
   
       5 . The method according to  claim 4  wherein the ionic liquid has a vapor pressure of less than about 0.1 mm/Hg at 25° C. 
   
   
       6 . The method according to  claim 5  wherein the ionic liquid has essentially no vapor pressure. 
   
   
       7 . The method according to  claim 1  wherein the thermal stability of the ionic liquid is from 150° C. to 400° C. 
   
   
       8 . The method according to  claim 7  wherein the thermal stability of the ionic liquid is from 200° C. to 300° C. 
   
   
       9 . The method according to  claim 1  wherein the ionic liquid has a melting point of less than 250° C., a vapor pressure less than about 1 mm/Hg at 25° C. and the thermal stability of the ionic liquid is from 150° C. to 400° C. 
   
   
       10 . The method according to  claim 1  wherein the anion of the ionic liquid is selected from the group consisting of Cl − , Br − , NO 2   − , NO 3   − , AlCl 4   − , BF 4   − , PF 6   − , CF 3 COO − , CF 3 SO 3   − , (CF 3 SO 2 ) 2 N − , OAc − , CuCl 3   − , GaBr 4   − , GaCl 4   − , and SbF 6   − . 
   
   
       11 . The method according to  claim 1  wherein the cation of the ionic liquid is selected from the group consisting of pyridinium, ammonium, imidazolium, phosphonium, and sulphonium. 
   
   
       12 . The method according to  claim 1  wherein the ionic liquid is selected from the group consisting of an imidazolium salt, pyridinium salt, ammonium salt, phosphonium salt, and sulphonium salt, and mixtures thereof. 
   
   
       13 - 23 . (canceled)