Removing an organic compound from an aqueous solution comprises (a) providing the aqueous solution containing the organic compound and a hydrophobic organic solution containing a liquid cation exchanger, where the liquid cation exchanger is hydrophobic, (b) contacting the aqueous solution and the organic solution, and (c) separating the organic solvent from the aqueous solution, where the organic compound is an ammonium compound (I) and the liquid cation exchanger is a fatty acid. Removing an organic compound from an aqueous solution comprises (a) providing the aqueous solution containing the organic compound and a hydrophobic organic solution containing a liquid cation exchanger, where the liquid cation exchanger is hydrophobic, (b) contacting the aqueous solution and the organic solution, and (c) separating the organic solvent from the aqueous solution, where the organic compound is an ammonium compound of formula (NH 3 +>-A-COOR 1>) (I) and the liquid cation exchanger is a fatty acid. R 1> : H, CH 3, C 2H 5or negative charge; and A : unsubstituted, linear at least 3C, preferably 8C-alkylene. An independent claim is included for a reaction mixture comprising the aqueous solution and the hydrophobic organic solution, where the liquid cation exchanger is a fatty acid with greater than 12 carbon atoms.