Patent ID: 7732494

Claim:
A method for recovering fine particles dispersed in an aqueous medium comprising, adding an ionic liquid, which does not dissolve substantially a dispersing aqueous medium, to the aqueous medium containing fine particles and transferring said fine particles from said aqueous medium to the ionic liquid, wherein the amount of the ionic liquid b mL to be added to 10 mL of the aqueous medium containing said fine particles by a mM dispersing concentration is in the range so as the ratio a/b is 0.05≦a/b<1.0,and wherein said ionic liquid is an organic ionic liquid selected from the group consisting of compounds represented by following formulae 1, wherein, R 3 and R 4 are an alkyl group of carbon number 1-7, n is an interger of 1-3, R 1 is an alkyl group which can possess a substitution group of carbon number 1-7, X − is selected from the group consisting of NO 3 − , (CF 3 SO 3 ) 2 N − , TFSI − , Cl − and SO 3 H − .