Superchaotropic ion flotation: A new concept for the extraction and separation of nanometer-sized ions by non-ionic surfactant-based foams

•The superchaotropic nature of the Krebbs anion, Mo36O1128−, is shown for the first time.•Polyoxometalates formed by varying pH/concentration do bind with non-ionic surfactants.•Ion separation is performed here for the first time by non-ionic surfactant foams.•Non-ionic surfactants affect the equilibria of formation of foam extractible polyoxometalates.•As a proof of concept, W and Mo were separated by using a polyethoxylated (non-ionic) surfactant.