The present application relates to a process for removing an organic compound having one or more positive charges from an aqueous solution, comprising the steps a) provision of the aqueous solution comprising the organic compound and of a hydrophobic organic solution which comprises a liquid cation exchanger, where the liquid cation exchanger is hydrophobic, and where the liquid cation exchanger has one or more negative charges and an overall negative charge, b) contacting the aqueous solution and the organic solution, and c) separating off the organic solution from the aqueous solution.