Characterization of uranium(VI) sorption by organobentonite

• Published in: Applied surface science 2010-06, Vol.256 (17), p.5416-5421
• Main Authors: Majdan, Marek, Pikus, Stanisław, Gajowiak, Agnieszka, Gładysz-Płaska, Agnieszka, Krzyżanowska, Halina, Żuk, Jerzy, Bujacka, Monika
• Format: Article
• Language: English
• Subjects: Absorption coefficient; Bentonite; Bromides; Cations; Condensed matter: electronic structure, electrical, magnetic, and optical properties; Condensed matter: structure, mechanical and thermal properties; Cross-disciplinary physics: materials science; rheology; Exact sciences and technology; Hexadecyltrimethylammonium bromide; Organobentonite; Physics; Sorbents; Sorption; Surface chemistry; Uranium
• ISSN: 0169-4332; 1873-5584
• DOI: 10.1016/j.apsusc.2009.12.123

The U(VI) sorption on the bentonite modified by hexadecyltrimethylammonium bromide (HDTMA) was studied in the concentration range: 0.0001–0.001 mol/dm 3 in the aqueous phase and in the pH range: 3–10. The experiments concerning the pH influence on the molar absorption coefficient c b of U(VI) in the bentonite phase showed that the species: UO 2 2+, UO 2(OH) +, UO 2(OH) 2 UO 2(OH) 3 −, UO 2(OH) 4 2−, (UO 2) 3(OH) 5 +, (UO 2) 3(OH) 7 −, present in the aqueous phase, are responsible for uranium sorption. Their sorption parameters K were determined and it is evident that for higher concentrations of HDTMA + cations in the bentonite phase, i.e. for b96–b157 bentonite, the presence of anionic species: UO 2(OH) 3 −, UO 2(OH) 4 2−, and (UO 2) 3(OH) 7 − in the aqueous phase results in the increase of U(VI) molar absorption coefficient c b in the sorbent phase.