Comparison of mass transfer coefficient approach and Nernst−Planck formulation in the reactive transport modeling of Co, Ni, and Ag removal by mixed-bed ion-exchange resins

International audienceExperiments performed under chemical and flow conditions representative of pressurized water reactors (PWR) primary fluid purification by ion exchange resins (Amberlite IRN9882) are modeled with the OPTIPUR code, considering 1D reactive transport in the mixed-bed column with convective/dispersive transport between beads and electrodiffusive transport within the boundary film around the beads. The effectiveness of the purification in these dilute conditions is highly related to film mass transfer restrictions, which are accounted for by adjustment of a common mass transfer coefficient (MTC) on the experimental initial leakage or modeling of species diffusion through the bead film by the Nernst−Planck equation. A detailed analysis of the modeling against experimental data shows that the Nernst−Planck approach with no adjustable parameters performs as well as, or better than, the MTC approach, particularly to simulate the chromatographic elution of silver by nickel and the subsequent enrichment of the solution in the former metal

Optimization of the arsenazo-III method for the determination of uranium in water and plant samples

International audienc

Sensing of the uranyl ion based on its complexation with bisphosphonate-capped gold nanoparticles

International audienceWe describe a sensing system that relies upon the formation of specific complexes between uranyl ion and bisphosphonate-capped gold nanoparticles. The ensuing concentration-dependent red-shift of surface plasmon resonance absorption allows the determination of uranyl ion concentration within the 1.5-15 ppm range

Use of fonctionnalized gold nanoparticles to assay uranium

The subject of the invention is the use of particular functionalized gold nanoparticles to determine the presence and/or assay the amount of uranium in a solution. After the functionalized gold nanoparticles have been placed in the solution, the assay may especially be carried out by spectrophotometry. The invention also relates to a kit that can be used for uranium assays in situ in the field

Predicting ion exchange resins decontamination factors - Experiments on synthetic primary coolant containing Ni, Co and Ag and modeling results

International audienc