Nanocomposites and nanomaterials

Composites containing graphene nanoparticles for removal of U(VI) compounds from water
Perlova O.V.1, Dzyazko Yu.S.2, Ogenko V.M.2, Ivanova I.S.1, Palchik A.V.2
1 Odessa I.I. Mechnikov National University, 2 Dvoryanska Str., 65082 Odesa, Ukraine
E-mail: inna_ivanova_2512@ukr.net
2 V.I. Vernadskii Institute of General and Inorganic Chemistry of the NAS of Ukraine, 32/34 Palladin ave., 03142 Kyiv, Ukraine

Earlier such nanomaterials as hydrated zirconium dioxide and zirconium hydrophosphate were used for modifying anion and cation exchange resins respectively, the composites were applied to removal of U(VI) compounds from water [1, 2]. In this work we have developed a number of nanomaterials based on mentioned ion-exchangers containing nanoparticles of oxidized graphene (GO). TEM analysis shows several types of particles forming the composites: (i) the inorganic primary nanoparticles (up to 20 nm) covered with GO nanoparticles (up to 4 nm), (ii) the inorganic nanoparticles, which are free from GO, (iii) the aggregates of GO nanoparticles. Specific surface area of the samples was 400 m2×g-1. Sorption of U(VI) cationic compounds from nitrate solutions was investigated within the pH interval of 2-8. As found, GO depresses sorption on oxide sorbent, since GO screens the surface of nanoparticles. At the same time, GO promotes sorption on phosphate-containing nanomaterials. After 4 h, the removal degree of UO22+ cations reaches 42-70% (phosphate without GO) and 35-38 % (phosphate containing GO) at the pH interval of 3-6. Under equilibrium conditions, most complete removal degree is achieved at the pH of 4-6 (phosphate-GO) or 8 (phosphate without GO). The nanocomposites can be recommended for modifying ion exchange resins and membranes.

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2.	Perlova O., Dzyazko Yu., Halutska I., Perlova N., Palchik A. Anion exchange resin modified with nanoparticles of hydrated zirconium dioxide for sorption of soluble U(VI) compounds // Springer Proc. Phys. − 2018. − V. 214. − Р. 3-15.