The reduction of Np(V) in groundwater rich in humic substances

Authors
Zeh, P Kim, JI Marquardt, CM Artinger, R
Citation
P. Zeh et al., The reduction of Np(V) in groundwater rich in humic substances, RADIOCH ACT, 87(1-2), 1999, pp. 23-28
Citations number
20
Categorie Soggetti
Inorganic & Nuclear Chemistry
Journal title
RADIOCHIMICA ACTA
ISSN journal
00338230 → ACNP
Volume
87
Issue
1-2
Year of publication
1999
Pages
23 - 28
Database
ISI
SICI code
0033-8230(1999)87:1-2<23:TRONIG>2.0.ZU;2-4
Abstract
The reduction of Np(V) to Np(IV) in one of the Gorleben aquifer systems con taining humic substances was investigated by absorption spectroscopy and ul trafiltration in the neutral pH range. Batch and column experiments were ca rried out to estimate the reduction behaviour under different experimental conditions. Natural humic substances in groundwater are found to cause the Np(V) reduction. The tetravalent neptunium thus produced appears to be a hu mic colloid-borne species that can be separated from water by ultrafiltrati on, while the original pentavalent neptunium is present as NpO2+ ion, Np(V) mono-carbonate and / or Np(V) humate depending on PH.