Np(V) uptake by various clays

In this work, we study different clay samples to examine the effect of structural features of clay minerals (2:1 and 1:1 structures), interlayer cations (Na/Ca/Li forms of montmorillonite), surface area and presence of accessory minerals (iron oxides, calcite, quartz) on Np(V) sorption at trace concentrations. Various techniques, e.g., XRD, XRF, DTG, FTIR, BET absorption and Mossbauer spectroscopy, were used to characterize these clays. The presence of iron oxide as an accessory mineral has a strong effect on Np(V) sorption. Sorption of Np(V) onto different clay minerals with different surface areas, interlayer cations and structures is very similar at a pH range of 4.5-11.5.