Comparison of three labeled silica nanoparticles used as tracers in transport experiments in porous media. Part II: transport experiments and modeling.
Three types of labeled silica nanoparticles were used in transport experiments in saturated sand. The goal of this study was to evaluate both the efficiency of labeling techniques (fluorescence (FITC), metal (Ag(0) core) and radioactivity ((110m)Ag(0) core)) in realistic transport conditions and the reactive transport of silica nanocolloids of variable size and concentration in porous media. Experimental results obtained under contrasted experimental conditions revealed that deposition in sand is controlled by nanoparticles size and ionic strength of the solution. A mathematical model is proposed to quantitatively describe colloid transport. Fluorescent labeling is widely used to study fate of colloids in soils but was the less sensitive one. Ag(0) labeling with ICP-MS detection was found to be very sensitive to measure deposition profiles. Radiolabeled ((110m)Ag(0)) nanoparticles permitted in situ detection. Results obtained with radiolabeled nanoparticles are wholly original and might be used for improving the modeling of deposition and release dynamics.
LTHE UMR 5564, Grenoble F-38041, France; CEA, Technological Research Division, LCSN, Grenoble F-38054, France.
Elsa
E
Vitorge
Stéphanie
S
Szenknect
Jean M-F
JM
Martins
Véronique
V
Barthès
Jean-Paul
JP
Gaudet
D003102:Colloids / Q000032:analysis / Q000737:chemistry; D005453:Fluorescence; D008956:Models, Chemical; D008962:Models, Theoretical; D053758:Nanoparticles / Q000032:analysis* / Q000737:chemistry; D009994:Osmolar Concentration; D016062:Porosity; D012822:Silicon Dioxide / Q000032:analysis* / Q000737:chemistry; D014874:Water Pollutants, Chemical / Q000032:analysis* / Q000737:chemistry
D003102:Colloids; D014874:Water Pollutants, Chemical; D012822:Silicon Dioxide
(Radio) labeled nanoparticles; Deposition; Modeling; Nanotracers; Release; Silica colloids; Transport in porous media