Abstract
The complexation between a well characterized soil humic acid (OkchunHA) and trivalent metal ions (Cm3+, Eu3+) was compared with that by the Gorleben aquatic humic acid (GohyHA) by carrying out the investigation under the same experimental conditions and with the use of the same instrumentation (time resolved laser fluorescence spectroscopy: TRLFS). The emission spectra (peak maxima: 601.2 nm) and two time components for the lifetime of fluorescence (70 μs and 142 μs) were found to be nearly the same, suggesting that the two Cm(III)-humates formed from two different humic acids are made of the similar chemical species. The calculated stability constants (Cm(III)-hu-mate: logβ = 6.01 ±0.05 1 mol-1; Eu(III)-humate: logβ = 6.05±0.23 1 mol-1) were found to be in good agreement with those obtained earlier in the GohyHA study, suggesting that the same thermodynamic description can be applied to both humic acids, provided 1:1 complex formation is assumed.
| Original language | English |
|---|---|
| Pages (from-to) | 185-190 |
| Number of pages | 6 |
| Journal | Radiochimica Acta |
| Volume | 69 |
| Issue number | 3 |
| DOIs | |
| State | Published - Jul 1995 |
Keywords
- Curium
- Europium
- Humate complexation
- Time-resolved laser fluorescence spectroscopy
- Ultrafiltration