Published online by Cambridge University Press: 25 February 2011
The sorption of americium(III) and neptunium(V) on geologic media has been measured under oxic conditions. The aqueous phase was generally a synthetic groundwater. The solid phase was a pure mineral, representative of crystalline granitic rocks. Altogether 40 minerals and rocks were used. The effects of parameters such as pH and ionic strength of the aqueous phase as well as cation exchange capacity and surface/mass ratio of the solid sorbent are discussed. The sorption mechanism in the environmental pH-range can be denoted as physical adsorption process, which is largely governed by pH and the speciation in the aqueous phase and to a less extent by the exchange capacity of the solid.