Speciation of Technetium in Sulfuric Acid/Hydrogen Sulfide Solutions

M. Ferrier , J. Roques (1) , F. Poineau , A. P. Sattelberger , J. Unger , K. R. Czerwinski

1 IPNO - Institut de Physique Nucléaire d'Orsay

The reaction between TcVII and H2S(g) in 12 M H2SO4 has been studied. This reaction produced a black solid and a brown supernate. The solid was analyzed by energy dispersive X-ray (EDX) and X-ray absorption fine structure (XAFS) spectroscopy and the results were consistent with the presence of Tc2S7. The speciation of technetium in the supernate was performed by UV/Visible and XAFS spectroscopy. Experiments showed that in 12 M H2SO4 an intermediate TcV sulfate complex was formed. Analysis indicated that the final complex present in solution was a polymeric species with a Tc-O-Tc core coordinated to sulfate ligands. Density Functional Theory (DFT) calculations showed that the proposed complexes were stable and that the theoretical structure was in good agreement with XAFS data.

Domaines: Chimie-Physique [physics.chem-ph]

M. Ferrier, J. Roques, F. Poineau, A. P. Sattelberger, J. Unger, et al.. Speciation of Technetium in Sulfuric Acid/Hydrogen Sulfide Solutions. European Journal of Inorganic Chemistry, 2014, 2014, pp.2046-2052. ⟨10.1002/ejic.201301410⟩. ⟨in2p3-00993356⟩