Carbonate effects on hexavalent uranium adsorption by iron oxyhydroxide

Research output: Contribution to journalArticlepeer-review

256 Scopus citations

Abstract

Carbonate dramatically affects the adsorption of uranium (U(VI)) onto iron hydroxides and its mobility in the natural environment. Batch tests, zeta potential measurements, and Fourier transform infrared (FTIR) spectroscopic studies were utilized to characterize the nature of U(VI) adsorption on ferrihydrite. Adsorption isotherms demonstrated that carbonate had a negative effect on U(VI) adsorption on ferrihydrite at pH >6. Zeta potential measurements indicated that U(VI) was adsorbed as a cationic species (SO-UO2+) in the absence of carbonate and as anionic U(VI) complexes in the presence of carbonate at neutral pH. FTIR spectroscopic measurement of adsorbed U(VI) suggested that it was retained as uranyl carbonate complexes in the presence of carbonate. An increase in carbonate concentration caused a shift in the antisymmetric stretching vibration of the uranyl (UO22+) U-O bond toward lower wavenumbers, which indicated an increasing carbonate effect in the adsorbed uranyl carbonate complexes. The adsorbed U(VI) species were successfully incorporated into a surface complexation model to describe the adsorption of U(VI) by ferrihydrite from artificial solutions and contaminated water.

Original languageEnglish
Pages (from-to)3619-3624
Number of pages6
JournalEnvironmental Science and Technology
Volume37
Issue number16
DOIs
StatePublished - 15 Aug 2003

Fingerprint

Dive into the research topics of 'Carbonate effects on hexavalent uranium adsorption by iron oxyhydroxide'. Together they form a unique fingerprint.

Cite this