Abstract This paper presents first investigations on a novel An(III), Ln(III), Cs(I) and Sr(II) co-extraction conceptual process using a CHON solvent composed of the calixarene crown-ether MAXCalix and the diglycolamide TODGA in a 1-octanol/kerosene diluent. The co-extraction is followed by a sequential stripping of (1) Cs(I) and Sr(II), (2) An(III) and (3) Ln(III).