Babakhani, P orcid.org/0000-0002-5318-4320 (2019) The impact of nanoparticle aggregation on their size exclusion during transport in porous media: One- and three-dimensional modelling investigations. Scientific Reports, 9 (1). 14071. ISSN 2045-2322
Abstract
Greater particle mobility in subsurface environments due to larger size, known as size exclusion, has been responsible for colloid-facilitated transport of groundwater contaminants. Although size exclusion is not expected for primary engineered nanoparticles (NP), they can grow in size due to aggregation, thereby undergoing size exclusion. To investigate this hypothesis, an accurate population balance modelling approach and other colloid transport theories, have been incorporated into a three-dimensional transport model, MT3D-USGS. Results show that incorporating aggregation into the transport model improves the predictivity of current theoretical and empirical approaches to NP deposition in porous media. Considering an artificial size-variable acceleration factor in the model, NP breakthrough curves display an earlier arrival when aggregation is included than without. Disregarding the acceleration factor, aggregation enhances NP mobility at regions close to the injection point at a field scale and causes their retention at greater distances through alteration of their diffusivities, secondary interaction-energy minima, and settling behaviour. This results in a change of residual concentration profiles from exponential for non-aggregating dispersions to non-monotonic for aggregating dispersions. Overall, aggregation, hitherto believed to hinder the migration of NP in subsurface porous media, may under certain physicochemical conditions enhance their mobilities and deliver them to further distances.
Metadata
Item Type: | Article |
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Authors/Creators: |
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Copyright, Publisher and Additional Information: | © The Author(s) 2019. This is an open access article under the terms of the Creative Commons Attribution 4.0 International (CC BY 4.0) (https://creativecommons.org/licenses/by/4.0/) |
Dates: |
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Institution: | The University of Leeds |
Academic Units: | The University of Leeds > Faculty of Environment (Leeds) > School of Earth and Environment (Leeds) > Earth Surface Science Institute (ESSI) (Leeds) |
Depositing User: | Symplectic Publications |
Date Deposited: | 13 Nov 2019 16:09 |
Last Modified: | 13 Nov 2019 16:09 |
Status: | Published |
Publisher: | Nature Research |
Identification Number: | 10.1038/s41598-019-50493-6 |
Open Archives Initiative ID (OAI ID): | oai:eprints.whiterose.ac.uk:153420 |