TY - JOUR

T1 - Time resolved pore scale monitoring of nanoparticle transport in porous media using synchrotron X-ray μ-CT

AU - Schiefler, Adrian Alexander

AU - Sørensen, Henning Osholm

AU - Bruns, Stefan

AU - Müter, Dirk

AU - Uesugi, Kentaro

AU - Tobler, Dominique Jeanette

N1 - Publisher Copyright: © 2023 The Royal Society of Chemistry.

PY - 2023

Y1 - 2023

N2 - Recently, we demonstrated the potential of synchrotron X-ray micro computed tomography (μ-CT) to visualise the spatial distribution of nanoparticle aggregates inside porous matrices. This paved the way for increasing our understanding of pore-scale nanoparticle retention processes. Here, we present the first 3D timelapse of nanoparticle retention in a sand packed column at the sub-micrometre scale and demonstrate the wealth of information that can be gained through accessing four dimensions, i.e. time and space. This includes i) visualisation of gradual pore space saturation with nanoparticles, ii) localisation of retention growth domains, iii) quantification of the growth of retained nanoparticle clusters, and iv) quantification of the dynamic re-mobilisation processes of retained nanoparticle clusters. The quantification revealed that the retention was primarily controlled by a ripening process but also showed a surprisingly large NP cluster re-mobilisation during injection (i.e., up to 50% of the retained NP were re-mobilised). Our results demonstrate that in situ monitoring of nanoparticle retention is technically feasible and will reveal novel details, likely even processes, of nanoparticle transport and retention at the pore scale.

AB - Recently, we demonstrated the potential of synchrotron X-ray micro computed tomography (μ-CT) to visualise the spatial distribution of nanoparticle aggregates inside porous matrices. This paved the way for increasing our understanding of pore-scale nanoparticle retention processes. Here, we present the first 3D timelapse of nanoparticle retention in a sand packed column at the sub-micrometre scale and demonstrate the wealth of information that can be gained through accessing four dimensions, i.e. time and space. This includes i) visualisation of gradual pore space saturation with nanoparticles, ii) localisation of retention growth domains, iii) quantification of the growth of retained nanoparticle clusters, and iv) quantification of the dynamic re-mobilisation processes of retained nanoparticle clusters. The quantification revealed that the retention was primarily controlled by a ripening process but also showed a surprisingly large NP cluster re-mobilisation during injection (i.e., up to 50% of the retained NP were re-mobilised). Our results demonstrate that in situ monitoring of nanoparticle retention is technically feasible and will reveal novel details, likely even processes, of nanoparticle transport and retention at the pore scale.

U2 - 10.1039/d3en00227f

DO - 10.1039/d3en00227f

M3 - Letter

AN - SCOPUS:85169553162

VL - 10

SP - 2224

EP - 2231

JO - Environmental Science: Nano

JF - Environmental Science: Nano

SN - 2051-8153

IS - 9

ER -