Rhenium has recently shown up as a useful  radioisotope in variety of clinical trials. At present the carrier –free Re-188 is obtained from W-188/Re-188 generators in which the tungsten-188 in form of sodium tungstenate W-188 solution is adsorbed on the alumina filling of generator column. A new approach to preparation of chromatographic column packing of tungsten-188/rhenium generators is application of nanocomposites obtained by mean of the sol-gel technique... A specific method for the  synthesis of these materials was elaborated at INCT. The initial stage of the process is preparation of the ascorbate- NH₄⁺- tungsten, next the separately prepared zirconyl or/and silicon sols are added gradually to the reaction mixture. After a gelation step, the gels are thermal treated at temperatures indicated by thermal analysis (500, 650, 800^oC).  This way the synthesis of nanocomposites  containing of  TiO₂-WO₃, ZrO₂-WO₃, ZrO₂-SiO₂-WO₃  at different ratios of oxides were carried out. The elution profile of generator column packed on  gels samples activated in nuclear reactor have been studied using as eluent 0,9% NaCl solution as an eluent. The best results of elution  ( profile and eluent purity ) appeared in the case of filling a chromatographic column by materials ;WO₃-ZrO₂ in which the oxides molar ratio was  1:2 and calcination temperature 500^oC and WO₃-TiO₂ with molecular ratio 1:2 and a calcination temperature of 650^oC. The samples containing WO₃-ZrO₂-SiO₂ did reveal satisfactory elution profile. For determination of structure of ZrO2-WO3 composites the neutron scattering and X-ray diffraction analysis have been applied. The gels at different molar ratio of oxides 1:1, 2:1, 2:3 and annealed at 500^o, 650^o,800^oC had been examined. The atomic ordering of the composites was studied by wide range scattering angle ( 10^o – 110^o ) neutron diffraction. The measurements were carried out with a double crystal monochromator diffractometry employing Cu single crystals with (200) reflection planes. The nanoscale structure of the composites was determined by the small angle neutron scattering in 0.1 nm^-1 – 1 nm^-1 region. The small angle neutron scattering was studied with λ= 0.237 nm neutrons monochromatized with double PG monochromator and filtered with 3 cm thick PG filter. In conclusion of experiments , we can state that the WO₃-ZrO₂ composites easy crystallize and the rate of process increases with the annealing temperature. In the composites annealed at 500^oC the inhomogenities of average diameter of 50 nm and highly warped boundary surface are found. For higher annealing temperatures the cylinder like particles are formed. Next the samples were analyzed by X-ray diffraction technique using  Cu  radiation and scanning range from 2Θ =3^o to 2Θ =90^o (step 0.02^o and rate 2^o/min). On the X-ray diffraction pattern WO₃-ZrO₂ (1:1, 1:2, 3:2) composites annealed at   500^oC practically no peaks are visible, materials are rather amorphous. After annealing at 650^oC,  few weak peaks beyond the background level are observed . The gels annealed at 800^oC are fully crystalline and contain both oxides as separate phases : WO₃ as a monoclinic form and ZrO₂  as the mixture of cubic and tetragonal phases. Acknowledgment: The work was supported by the research grant No 3 TO9B 042 29 of the Polish Ministry of Science and Education

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