Nanoparticle transport in saturated porous medium using magnetic resonance imaging

Transport study of nanoparticle (NP) through matrix flow dominated aquifer sand and soils have significant influence in natural systems. To quantify the transport behaviour, magnetic resonance imaging (MRI) was used to image the iron oxide based nanoparticle, Molday ION (carboxyl terminated) through saturated sandstone rock core. T-2-weighted images were acquired and the changes in image intensity were calibrated to get a quantitative concentration profiles at various time intervals. These profiles were evaluated through CXTFIT transport model to estimate the transport parameters. These parameters are estimated at various points along the length of the column while classical breakthrough curve analysis cannot provide these details. NP-surface interactions were investigated using DLVO (Derjaguin-Landau-Verwey-Overbeek) theory. The dispersion coefficients (2.55-1.21 x 10(-7) m(2)/s) were found to be decrease with distance, deposition rate constant k (6.70-9.13 x 10(-4) (1/s)) and fast deposition rate constant k(fast) (4.32-8.79 x 10(-2) (1/s)) were found to be increase with distance. These parameter variations over length will have a scaling up impact in developing transport models for environmental remediation and risk assessment schemes. (C) 2015 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY license.