How mobile is iodide in the Callovo-Oxfordian claystones under experimental conditions close to the in situ ones?

摘要: Abstract The iodide behaviour towards the Callovo–Oxfordian claystone was studied using batch and diffusion experiments under conditions which limited artefacts cited in literature to be responsible for uptake (i.e. were carried out anoxic with N 2 /CO atmosphere a monitoring of iodine redox-state). results show that all radioactive 125 I − , no measurable activity IO 3 is known have higher affinity rock than iodide. Moreover, revealed sorption, independently initial concentration (from 10 − 6 − 3  mol L − 1 ) contact time (up 106 days). Conversely, indicated weak but retention. through-diffusion led distribution ratio values only significant ( R D  ~ 0.05 mL g concentration ≤ 10 − 4 . Higher estimated from out-diffusion experiments, ranging about 0.05 mL g an 0.14 mL g lowest one. A retention phenomenon could reversible kinetically-controlled proposed explain differences extent retardation two types experiments.