Patent ID: 7825259

Claim:
A method for preparing halogen-free ionic liquids, the method comprising the following steps: i) reacting 1-alkyl (C 1 -C 18 )-imidazolium with alkyl (C 1 -C 18 ) alkane (C 1 -C 18 ) sulfonates or with alkyl (C 1 -C 18 ) trifluoromethanesulfonate, wherein the 1-alkyl (C 1 -C 18 )-imidazolium is alkylated; ii) reacting, in a metathesis reaction in an aqueous solution, alkyl (C 1 -C 18 ) alkane (C 1 -C 18 ) sulfonates with alkaline metal salts containing BF 4 , CF 3 SO 3 , (CF 3 SO 2 ) 2 N, or (CF 3 CF 2 ) 3 PF 3 ; and iii) obtaining a halogen-free ionic liquid from steps (i) and (ii).