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Information × Registration Number 0223U001369, (0122U000866) , R & D reports Title Ecological sorbents based on mechanochemically activated clay minerals for radionuclide removal popup.stage_title Дослідження впливу механохімічної активації з використанням катіонних поверхнево-активних речовин (гексадецилтриметиламоній бромід) на особливості і механізм зміни структури бентоніту з метою управління їх сорбційною активністю. Head Romanova Iryna V., Доктор хімічних наук Registration Date 28-01-2023 Organization State organization Institute of Sorption and Endoecology Problems of the National Academy of Sciences of Ukraine popup.description1 Traditional methods of modifying clay minerals in the aquatic environment are quite time consuming. To save time and cost of modification of sorption materials and reduce their negative impact on the environment, we will perform mechanochemical modification of clay minerals by their energy-intensive dispersion with the simultaneous addition of surfactants. The influence of conditions of mechanochemical modification of clay minerals (first of all, bentonite) on their sorption properties in relation to uranium, cesium and strontium will be established, physicochemical parameters influencing their sorption properties will be determined. popup.description2  Environmentally safe methods of obtaining sorption materials using energetic dispersion have been developed. The physicochemical characteristics of the obtained sorbents, which determine their sorption properties, have been determined. It is precisely during the mechanochemical activation of montmorillonite that it is possible to achieve a sufficiently high degree of increase in SBET of the surface (from 80.3 m²/g to 146.8 m²/g). It is shown that the sorption properties of the obtained materials with respect to uranium, cesium and strontium compounds depend on the conditions of mechanochemical and acid activation, the time of processing clay minerals, pH, the concentration of radionuclides in the solution, the presence of complexing agents, etc. The study of the processes of sorption of uranium ions from aqueous solutions showed that the maximum sorption is reached on activated samples within 2 hours. The sorption values ​​for such samples are more than 2.5 times higher than the original MMT values, which is due to particle fragmentation and an increase in surface area. It is shown that the improvement of the sorption indicators of Cs+ and Sr2+ ions is correlated with the increase in the duration of MXA. The mechanisms of sorption of radionuclides on the surface of the obtained sorbents were determined. It has been confirmed that the ditrigonal holes of the silica grids on the MMT surface are proportional to the size of the large cations of the alkali metal, which is decisive in increasing its selectivity to cesium ions. A composite fibrous sorption material with high selectivity for cesium and strontium ions was obtained, and cesium ions are better sorbed by the sodium form of the sorbent (Kd = 6200), and strontium ions by the ammonium form (Kd = 88700). Product Description popup.authors Zhuravlev Ihor Z. Zakutevskyi Oleh I. Kovalchuk Iryna A. Kovtun Maria F. Kotynska Liudmyla Yo. Mameteva Yevheniia H. Tytarenko Maryna V. Trykhlib Volodymyr A. Farbun Iryna A. Khodakovska Tetiana A. Tsyba Mykola M. popup.nrat_date 2023-01-28 Close