Processing and/or operating machine comprising an ionic liquid as the operating liquid

Abstract

The invention relates to a processing or working machine comprising a liquid as the operating liquid wherein the invention is characterized in that an ionic liquid constitutes said operating liquid. The invention also relates to the use of operating fluids in processing or working machines, wherein an ionic liquid constitutes the operating liquid and is used, in particular, as a lubricating fluid, barrier fluid, sealing fluid, or a pressure transmission fluid.

1 . An operating machine selected from the group consisting of: 
 a) a gas conveying machine characterized in that it comprises an ionic liquid as lubricating and barrier fluid;    b) a hydraulic diaphragm pump characterized in that it comprises an ionic liquid as hydraulic fluid;    c) a liquid ring vacuum pump characterized in that it comprises an ionic liquid as ring liquid; and    d) a piston machine characterized in that it is equipped with a piston, oscillating in a cylinder, in the form of a fluid piston or a fluid master piston arranged in front which fluid comprises an ionic liquid and, as a result of its oscillating movement, conveys a gas and/or non-miscible fluid of low density or a fluid of high density.    
     
     
         2 . (canceled)  
     
     
         3 . (canceled)  
     
     
         4 . (canceled)  
     
     
         5 . The operating machine of  claim 1 , all limitations of which are incorporated by reference, characterized in that the ionic liquid is a compound, or mixture of two or more compounds, of the formula  
         [cation] [anion],  
       wherein:  
       cation is selected from the group consisting of: 
 a quaternary ammonium cation having the general formula  
   [NR 1 R 2 R 3 R] + ,  
 or a phosphonium cation having the general formula  
   [PR 1 R 2 R 3 R] + ,  
 or an imidazolium cation having the general formula  
                     
 in which the imidazole nucleus may be substituted by at least one group selected from  
 C 1 -C 6  alkyl groups, C 1 -C 6  alkoxy groups, C 1 -C 6  aminoalkyl groups, C 5 -C 12  aryl groups or C 5 -C 12  aryl C 1 -C 6  alkyl groups,  
 pyridinium cation having the general formula  
                     
 in which the pyridine nucleus may be substituted by at least one group selected from C 1 -C 6  alkyl groups, C 1 -C 6  alkoxy groups, C 1 -C 6  aminoalkyl groups, C 5 -C 12  aryl groups or C 5 -C 12  aryl-C 1 -C 6  alkyl groups, 
 pyrazolium cation having the general formula  
                     
 in which the pyrazole nucleus may be substituted by at least one group selected from C 1 -C 6  alkyl groups, C 1 -C 6  alkoxy groups, C 1 -C 6  aminoalkyl groups, C 5 -C 12  aryl groups or C 5 -C 12  aryl-C 1 -C 6  alkyl groups, and  
 triazolium cation having the general formula  
                     
 in which the triazole nucleus may be substituted by at least one group selected from C 1 -C 6  alkyl groups, C 1 -C 6  alkoxy groups, C 1 -C 6  aminoalkyl groups, C 5 -C 12  aryl groups or C 5 -C 12  aryl-C 1 -C 6  alkyl groups, and  
 
 the radicals R 1 , R 2 , R 3  independently from each other are selected from the group consisting of:  
 hydrogen;  
 linear or branched, saturated or unsaturated, aliphatic or alicyclic alkyl groups having 1 to 20 carbon atoms;  
 heteroaryl groups, heteroaryl C 1 -C 6  alkyl groups having 3 to 8 carbon atoms in the heteroaryl radical and at least one hetero atom selected from N, O and S, which can be substituted by at least one group selected from C 1 -C 6  alkyl groups and/or halogen atoms; and  
 aryl groups, aryl C 1 -C 6  alkyl groups having 5 to 12 carbon atoms in the aryl radical which, if necessary, may be substituted by at least one C 1 -C 6  alkyl group and/or a halogen atom; and  
 the radical R is selected from  
 linear or branched, saturated or unsaturated, aliphatic or alicyclic alkyl groups having 1 to 20 carbon atoms;  
 heteroaryl C 1 -C 6  alkyl group with 3 to 8 carbon atoms in the aryl radical and at least one hetero atom selected from N, O and S, which may be substituted by at least one C 1 -C 6  alkyl group and/or halogen atoms;  
 aryl C 1 -C 6  alkyl groups having 5 to 12 carbon atoms in the aryl radical which may optionally be substituted by at least one C 1 -C 6  alkyl group and/or a halogen atom; and  
 anion is selected from the group consisting of [PF 6 ] − , [BF 4 ] − , [CF 3 CO 2 ] − , [CF 3 SO 3 ] − , [(CF 3 SO 2 ) 2 N] − , [(CF 3 SO 2 )(CF 3 COO)N] − , [R 4 —SO 3 ] − , [R 4 —O—SO 3 ] − , [R 4 —COO] − , Cl − , Br − , I − , [NO 3 ] − , [N(CN) 2 ] − , [HSO 4 ] −  and [R 4 R 5 PO 4 ] − , wherein:  
 the radicals R 4  and R 5  independently from each other are selected from the group consisting of:  
 hydrogen;  
 linear or branched, saturated or unsaturated, aliphatic or alicyclic alkyl groups having 1 to 20 carbon atoms;  
 heteroaryl groups, heteroaryl C 1 -C 6  alkyl groups having 3 to 8 carbon atoms in the hetero aryl radical and at least one hetero atom selected from N, O and S which may be substituted by at least one group selected from C 1 -C 6  alkyl groups and/or halogen atoms; and  
 aryl groups, aryl C 1 -C 6  alkyl groups having 5 to 12 carbon atoms in the aryl radical which may be substituted by at least one C 1 -C 6  alkyl group and/or a halogen atom.  
 
     
     
         6 . The operating machine according to  claim 5 , all limitations of which are incorporated by reference, characterized in that the ionic liquid used as operating liquid is selected from the group consisting of 1-butyl-3-methylimidazolium tetrafluoroborate, 1-butyl-3-methylimidazolium hexafluorophosphate, 1-ethyl-3-methylimidazolium ethyl sulphate, 1-ethyl-3-methylimidazolium bistrifluoromethane sulfonyl amide, 3-methyl-1-ethylpyridinium ethyl sulphate, and butyl trimethyl phosphonium dimethyl phosphate or a combination or two or more thereof.  
     
     
         7 . The operating machine according to  claim 5 , all limitations of which are incorporated by reference, characterized in that the ionic liquid used as operating liquid is selected from the group consisting 1-alkyl-3-alkyl-imidazolium tetrafluoroborate, 1-alkyl-3-alkyl-imidazolium hexafluorophosphate, 1-alkyl-3-alkyl-imidazolium alkyl sulfate, 1-alkyl-3-alkyl-imidazolium alkyl sulfonate, 1-alkyl-3-alkyl-imidazolium trifluoroalkyl sulfonate, 1-alkyl-3-alkyl-imidazolium bistrifluoromethane sulfonyl amide, 1-alkyl-3-alkyl-imidazolium dialkyl phosphate, tetraalkylphosphonium dialkyl phosphate, 1-alkyl-3-alkyl-pyridinium tetrafluoroborate, 1-alkyl-3-alkyl-pyridinium hexafluorophosphate, 1-alkyl-3-alkyl-pyridinium alkyl sulfate, 1-alkyl-3-alkyl-pyridinium alkyl sulfonate, 1-alkyl-3-alkyl-pyridinium trifluoroalkyl sulfonate, 1-alkyl-3-alkyl-pyridinium bistrifluoromethane sulfonyl amide, 1-alkyl-3-alkyl-pyridinium dialkyl phosphate, N-alkyl-N-alkyl-pyrolidinium tetrafluoroborate, N-alkyl-N-alkyl-pyrolidinium hexafluorophosphate, N-alkyl-N-alkyl-pyrolidinium alkyl sulfate, N-alkyl-N-alkyl-pyrolidinium alkyl sulfonate, 1 N-alkyl-N-alkyl-pyrolidinium trifluoroalkyl sulfonate, N-alkyl-N-alkyl-pyrolidinium bistrifluoromethane sulfonyl amide, N-alkyl-N-alkyl-pyrolidinium dialkyl phosphate, trialkylsulfonium bistrifluoromethane sulfonyl amide, and a combination of two or more thereof.  
     
     
         8 . The operating machine according to  claim 5 , all limitations of which are incorporated by reference, wherein the ionic liquid possesses one or a combination of two, three, four or more of the following properties: a) a vapor pressure of less than 10 −3  mbar; b) a melting point of less than 20° C. or less than 100° C.; c) a viscosity of no more than 1500 mPas and or between 50 and 400 mPas; d) a flash point of no less than 150° C.; e) a compressibility of no more than 0.7 volume loss per 100 bar; f) an electric resistance of 0.25-4 kOhm*cm.  
     
     
         9 . The operating machine according to  claim 5 , all limitations of which are incorporated by reference, wherein the ionic liquid further comprises one or more additives selected from the group consisting of anti-wear additive, friction modifier, rust and corrosion inhibitor, antioxidant, dispersant, detergent, anti-foaming agent, and pour point depressant.  
     
     
         10 . A method of employing an operating liquid in a gas conveying machine, hydraulic diaphragm pump, liquid ring vacuum pump screw pump, or piston-containing machine comprising employing an ionic liquid as the operating liquid, whereby the ionic liquid serves as a lubricating fluid, barrier fluid, sealing fluid, hydraulic fluid, ring liquid, fluid piston and/or pressure transfer fluid.  
     
     
         11 . The method of  claim 10 , all limitations of which are incorporated by reference, characterized in that the ionic liquid is used in a gas conveying machine as a lubricating fluid and barrier fluid.  
     
     
         12 . The method of  claim 10 , all limitations of which are incorporated by reference, characterized in that the ionic liquid is used in a hydraulic diaphragm pump as a hydraulic fluid.  
     
     
         13 . The method of  claim 10 , all limitations of which are incorporated by reference, characterized in that the ionic liquid is used in a liquid ring vacuum pump as a ring liquid, thereby extending the operating range of the pump into the fine vacuum range.  
     
     
         14 . The method of  claim 10 , all limitations of which are incorporated by reference, characterized in that the ionic liquid is used in a piston-containing machine as a fluid piston oscillating in a cylinder which, as a result of its oscillating movement, is capable of conveying a gas and/or a non-miscible fluid of low density or a fluid of high density.  
     
     
         15 . A method of equipping a machine comprising: including an ionic liquid in the machine as an operating fluid in the machine, wherein: the machine is selected from the group consisting of gas conveying machine, hydraulic diaphragm pump, liquid ring vacuum pump, screw pump, and piston-containing machine; and the ionic liquid serves as a lubricating fluid, barrier fluid, sealing fluid, hydraulic fluid, ring liquid, fluid piston and/or pressure transfer fluid.  
     
     
         16 . The method according to  claim 10 , all limitations of which are incorporated by reference, wherein the ionic liquid is a compound, or mixture of two or more compounds, of the formula  
         [cation] [anion],  
       wherein:  
       cation is selected from the group consisting of: 
 a quaternary ammonium cation having the general formula  
   [NR 1 R 2 R 3 R] + ,  
 or a phosphonium cation having the general formula  
   [PR 1 R 2 R 3 R] + ,  
 or an imidazolium cation having the general formula  
                     
 in which the imidazole nucleus may be substituted by at least one group selected from C 1 -C 6  alkyl groups, C 1 -C 6  alkoxy groups, C 1 -C 6  aminoalkyl groups, C 5 -C 12  aryl groups or C 5 -C 12  aryl C 1 -C 6  alkyl groups,  
 pyridinium cations having the general formula  
                     
 in which the pyridine nucleus may be substituted by at least one group selected from C 1 -C 6  alkyl groups, C 1 -C 6  alkoxy groups, C 1 -C 6  aminoalkyl groups, C 5 -C 12  aryl groups or C 5 -C 12  aryl-C 1 -C 6  alkyl groups,  
 pyrazolium cations having the general formula  
                     
 in which the pyrazole nucleus may be substituted by at least one group selected from C 1 -C 6  alkyl groups, C 1 -C 6  alkoxy groups, C 1 -C 6  aminoalkyl groups, C 5 -C 12  aryl groups or C 5 -C 12  aryl-Cl-C 6  alkyl groups,  
 and triazolium cations having the general formula  
                     
 in which the triazole nucleus may be substituted by at least one group selected from C 1 -C 6  alkyl groups, C 1 -C 6  alkoxy groups, C 1 -C 6  aminoalkyl groups, C 5 -C 12  aryl groups or C 5 -C 12  aryl-C 1 -C 6  alkyl groups,  
 and the radicals R 1 , R 2 , R 3  independently from each other are selected from the group consisting of: 
 hydrogen;  
 linear or branched, saturated or unsaturated, aliphatic or alicyclic alkyl groups having 1 to 20 carbon atoms;  
 heteroaryl groups, heteroaryl C 1 -C 6  alkyl groups having 3 to 8 carbon atoms in the heteroaryl radical and at least one hetero atom selected from N, O and S, which can be substituted by at least one group selected from C 1 -C 6  alkyl groups and/or halogen atoms; and  
 aryl groups, aryl C 1 -C 6  alkyl groups having 5 to 12 carbon atoms in the aryl radical which, if necessary, may be substituted by at least one C 1 -C 6  alkyl group and/or a halogen atom; and  
 
 the radical R is selected from 
 linear or branched, saturated or unsaturated, aliphatic or alicyclic alkyl groups having 1 to 20 carbon atoms;  
 heteroaryl C 1 -C 6  alkyl group with 3 to 8 carbon atoms in the aryl radical and at least one hetero atom selected from N, O and S, which may be substituted by at least one C 1 -C 6  alkyl group and/or halogen atoms;  
 aryl C 1 -C 6  alkyl groups having 5 to 12 carbon atoms in the aryl radical which may optionally be substituted by at least one C 1 -C 6  alkyl group and/or a halogen atom; and  
 
 anion is selected from the group consisting of [PF 6 ] − , [BF 4 ] − , [CF 3 CO 2 ] − , [CF 3 SO 3 ] − , [(CF 3 SO 2 ) 2 N] − , [(CF 3 SO 2 )(CF 3 COO)N] − , [R 4 —SO 3 ] − , [R 4 —O—SO 3 ] − , [R 4 —COO] 31  , Cl − , Br − , I − , [NO 3 ] − , [N(CN) 2 ] − , [HSO 4]   −  and [R 4 R 5 PO 4 ] − , wherein:  
 the radicals R 4  and R 5  independently from each other are selected from the group consisting of: 
 hydrogen;  
 linear or branched, saturated or unsaturated, aliphatic or alicyclic alkyl groups having 1 to 20 carbon atoms;  
 heteroaryl groups, heteroaryl C 1 -C 6  alkyl groups having 3 to 8 carbon atoms in the hetero aryl radical and at least one hetero atom selected from N, O and S which may be substituted by at least one group selected from C 1 -C 6  alkyl groups and/or halogen atoms; and  
 aryl groups, aryl C 1 -C 6  alkyl groups having 5 to 12 carbon atoms in the aryl radical which may be substituted by at least one C 1 -C 6  alkyl group and/or a halogen atom.  
 
 
     
     
         17 . The method according to  claim 16 , all limitations of which are incorporated by reference, characterized in that the ionic liquid is selected from the group consisting of 1-butyl-3-methylimidazolium tetrafluoroborate, 1-butyl-3-methylimidazolium hexafluorophosphate, 1-ethyl-3-methylimidazolium ethyl sulphate, 1-ethyl-3-methylimidazolium bistrifluoromethane sulfonyl amide, 3-methyl-1-ethyl-pyridinium ethyl sulphate, and butyl trimethyl phosphonium dimethyl phosphate or a combination of two or more thereof.  
     
     
         18 . The method according to  claim 16 , all limitations of which are incorporated by reference, characterized in that the ionic liquid is selected from the group consisting 1-alkyl-3-alkyl-imidazolium tetrafluoroborate, 1-alkyl-3-alkyl-imidazolium hexafluorophosphate, 1-alkyl-3-alkyl-imidazolium alkyl sulfate, 1-alkyl-3-alkyl-imidazolium alkyl sulfonate, 1-alkyl-3-alkyl-imidazolium trifluoroalkyl sulfonate, 1-alkyl-3-alkyl-imidazolium bistrifluoromethane sulfonyl amide, 1-alkyl-3-alkyl-imidazolium dialkyl phosphate, tetraalkylphosphonium dialkyl phosphate, 1-alkyl-3-alkyl-pyridinium tetrafluoroborate, 1-alkyl-3-alkyl-pyridinium hexafluorophosphate, 1-alkyl-3-alkyl-pyridinium alkyl sulfate, 1-alkyl-3-alkyl-pyridinium alkyl sulfonate, 1-alkyl-3-alkyl-pyridinium trifluoroalkyl sulfonate, 1-alkyl-3-alkyl-pyridinium bistrifluoromethane sulfonyl amide, 1-alkyl-3-alkyl-pyridinium dialkyl phosphate, N-alkyl-N-alkyl-pyrolidinium tetrafluoroborate, N-alkyl-N-alkyl-pyrolidinium hexafluorophosphate, N-alkyl-N-alkyl-pyrolidinium alkyl sulfate, N-alkyl-N-alkyl-pyrolidinium alkyl sulfonate, 1 N-alkyl-N-alkyl-pyrolidinium trifluoroalkyl sulfonate, N-alkyl-N-alkyl-pyrolidinium bistrifluoromethane sulfonyl amide, N-alkyl-N-alkyl-pyrolidinium dialkyl phosphate, trialkylsulfonium bistrifluoromethane sulfonyl amide, and a combination of two or more thereof.  
     
     
         19 . The method according to  claim 16 , all limitations of which are incorporated by reference, wherein the ionic liquid possesses one or a combination of two, three, four or more of the following properties: a) a vapor pressure of less than 10-3 mbar; b) a melting point of less than 20° C. or less than 100° C.; c) a viscosity of no more than 1500 mPas and or between 50 and 400 mPas; d) a flash point of no less than 150° C.; 
 e) a compressibility of no more than 0.7 volume loss per 100 bar; f) an electric resistance of 0.25-4 kOhm*cm.    
     
     
         20 . The method according to  claim 16 , all limitations of which are incorporated by reference, wherein the ionic liquid further comprises one or more additives selected from the group consisting of anti-wear additive, friction modifier, rust and corrosion inhibitor, antioxidant, dispersant, detergent, anti-foaming agent, and pour point depressant.  
     
     
         21 . The method according to  claim 15 , wherein the ionic liquid is a compound, or mixture of two or more compounds, of the formula  
         [cation] [anion],  
       wherein: 
 cation is selected from the group consisting of: 
 a quaternary ammonium cation having the general formula  
   [NR  1 R 2 R 3 R] + ,  
 or a phosphonium cation having the general formula  
   [PR 1 R 2 R 3 R] + ,  
 or an imidazolium cation having the general formula  
                   
in which the imidazole nucleus may be substituted by at least one group selected from C 1 -C 6  alkyl groups, C 1 -C 6  alkoxy groups, C 1 -C 6  aminoalkyl groups, C 5 -C 12  aryl groups or C 5 -C 12  aryl C 1 -C 6  alkyl groups,  
 pyridinium cations having the general formula  
                     
 in which the pyridine nucleus may be substituted by at least one group selected from C 1 -C 6  alkyl groups, C 1 -C 6  alkoxy groups, C 1 -C 6  aminoalkyl groups, C 5 -C 12  aryl groups or C 5 -C 12  aryl-C 1 -C 6  alkyl groups,  
 pyrazolium cations having the general formula  
                     
 in which the pyrazole nucleus may be substituted by at least one group selected from C 1 -C 6  alkyl groups, C 1 -C 6  alkoxy groups, C 1 -C 6  aminoalkyl groups, C 5 -C 12  aryl groups or C 5 -C 12  aryl-C 1 -C 6  alkyl groups,  
 
 and triazolium cations having the general formula  
                     
 in which the triazole nucleus may be substituted by at least one group selected from C 1 -C 6  alkyl groups, C 1 -C 6  alkoxy groups, C 1 -C 6  aminoalkyl groups, C 5 -C 12  aryl groups or C 5 -C 12  aryl-C 1 -C 6  alkyl groups, 
 and the radicals R 1 , R 2 , R 3  independently from each other are selected from the group consisting of:  
 hydrogen;  
 linear or branched, saturated or unsaturated, aliphatic or alicyclic alkyl groups having 1 to 20 carbon atoms;  
 heteroaryl groups, heteroaryl C 1 -C 6  alkyl groups having 3 to 8 carbon atoms in the heteroaryl radical and at least one hetero atom selected from N, O and S, which can be substituted by at least one group selected from C 1 -C 6  alkyl groups and/or halogen atoms; and  
 aryl groups, aryl C 1 -C 6  alkyl groups having 5 to 12 carbon atoms in the aryl radical which, if necessary, may be substituted by at least one C 1 -C 6  alkyl group and/or a halogen atom; and  
 the radical R is selected from  
 linear or branched, saturated or unsaturated, aliphatic or alicyclic alkyl groups having 1 to 20 carbon atoms;  
 heteroaryl C 1 -C 6  alkyl group with 3 to 8 carbon atoms in the aryl radical and at least one hetero atom selected from N, O and S, which may be substituted by at least one C 1 -C 6  alkyl group and/or halogen atoms;  
 aryl C 1 -C 6  alkyl groups having 5 to 12 carbon atoms in the aryl radical which may optionally be substituted by at least one C 1 -C 6  alkyl group and/or a halogen atom; and  
 anion is selected from the group consisting of [PF 6 ] − , [BF 4 ] − , [CF 3 CO 2 ] − , [CF 3 SO 3 ] − , [(CF 3 SO 2 ) 2 N] − , [(CF 3 SO 2 )(CF 3 COO)N] − , [R 4 —SO 3 ] − , [R 4 —O—SO 3 ] − , [R 4 —COO] − , Cl − , Br − , I − , [NO 3 ] − , [N(CN) 2 ] − , [HSO 4 ] −  and [R 4 R 5 PO 4 ] − , wherein:  
 the radicals R 4  and R 5  independently from each other are selected from the group consisting of:  
 hydrogen;  
 linear or branched, saturated or unsaturated, aliphatic or alicyclic alkyl groups having 1 to 20 carbon atoms;  
 heteroaryl groups, heteroaryl C 1 -C 6  alkyl groups having 3 to 8 carbon atoms in the hetero aryl radical and at least one hetero atom selected from N, O and S which may be substituted by at least one group selected from C 1 -C 6  alkyl groups and/or halogen atoms; and  
 aryl groups, aryl C 1 -C 6  alkyl groups having 5 to 12 carbon atoms in the aryl radical which may be substituted by at least one C 1 -C 6  alkyl group and/or a halogen atom.  
 
 
     
     
         22 . The method according to  claim 21 , all limitations of which are incorporated by reference, characterized in that the ionic liquid is selected from the group consisting of 1-butyl-3-methylimidazolium tetrafluoroborate, 1-butyl-3-methylimidazolium hexa-fluorophosphate, 1-ethyl-3-methylimidazolium ethyl sulphate, 1-ethyl-3-methylimidazolium bistrifluoromethane sulfonyl amide, 3-methyl-1-ethylpyridinium ethyl sulphate, and butyl trimethyl phosphonium dimethyl phosphate or a combination of two or more thereof.  
     
     
         23 . The method according to  claim 21 , all limitations of which are incorporated by reference, characterized in that the ionic liquid is selected from the group consisting 1-alkyl-3-alkyl-imidazolium tetrafluoroborate, 1-alkyl-3-alkyl-imidazolium hexafluorophosphate, 1-alkyl-3-alkyl-imidazolium alkyl sulfate, 1-alkyl-3-alkyl-imidazolium alkyl sulfonate, 1-alkyl-3-alkyl-imidazolium trifluoroalkyl sulfonate, 1-alkyl-3-alkyl-imidazolium bistrifluoromethane sulfonyl amide, 1-alkyl-3-alkyl-imidazolium dialkyl phosphate, tetraalkylphosphonium dialkyl phosphate, 1-alkyl-3-alkyl-pyridinium tetrafluoroborate, 1-alkyl-3-alkyl-pyridinium hexafluorophosphate, 1-alkyl-3-alkyl-pyridinium alkyl sulfate, 1-alkyl-3-alkyl- pyridinium alkyl sulfonate, 1-alkyl-3-alkyl-pyridinium trifluoroalkyl sulfonate, 1-alkyl-3-alkyl-pyridinium bistrifluoromethane sulfonyl amide, 1-alkyl-3-alkyl-pyridinium dialkyl phosphate, N-alkyl-N-alkyl-pyrolidinium tetrafluoroborate, N-alkyl-N-alkyl-pyrolidinium hexafluorophosphate, N-alkyl-N-alkyl-pyrolidinium alkyl sulfate, N-alkyl-N-alkyl-pyrolidinium alkyl sulfonate, 1 N-alkyl-N-alkyl-pyrolidinium trifluoroalkyl sulfonate, N-alkyl-N-alkyl-pyrolidinium bistrifluoromethane sulfonyl amide, N-alkyl-N-alkyl-pyrolidinium dialkyl phosphate, trialkylsulfonium bistrifluoromethane sulfonyl amide, and a combination of two or more thereof.  
     
     
         24 . The method according to  claim 21 , all limitations of which are incorporated by reference, wherein the ionic liquid possesses one or a combination of two, three, four or more of the following properties: a) a vapor pressure of less than 10 −3  mbar; b) a melting point of less than 20° C. or less than 100° C.; c) a viscosity of no more than 1500 mPas and or between 50 and 400 mPas; d) a flash point of no less than 150° C.; e) a compressibility of no more than 0.7 volume loss per 100 bar; f) an electric resistance of 0.25-4 kOhm*cm.  
     
     
         25 . The method according to  claim 21 , all limitations of which are incorporated by reference, wherein the ionic liquid further comprises one or more additives selected from the group consisting of anti-wear additive, friction modifier, rust and corrosion inhibitor, antioxidant, dispersant, detergent, anti-foaming agent, and pour point depressant.