The thermal desorption of molybdenum(VI)-oxide from an inorganic adsorber matrix is an efficient new procedure for the final purification of fission molybdenum from inorganic and organic impurities. The investigations presented in this paper served to find out suitable thermally resistant inorganic ion exchangers and practical loading conditions for the preceding chromatographic sorption of molybdate anions from the process solution, in batch distribution experiments the influence of HN03-molarity, Mo-concentration and molybdenum loading on the Mo-sorption of Al2O3, SnO2, MnO2and Sb2O5is described in terms of their retention capacities and distribution coefficients. It could be confirmed that the retention capacity - as expected -depends strongly on the specific surface area, crystallinity and acidity of the oxide. AL2O3and SnO2with capacities of 30 and 4.7 mg Mo/g ion exchanger, respectively, proved to be superior to MnO2and Sb2O5owing to their faster Mo-sorption and better stability against abrasion.