Abstract
Iron oxide and iron nanoparticles (NPs) have been used effectively for environmental remediation, but are limited in their applications by strong retention in groundwater-saturated porous media. For example, delivery of NPs to large groundwater reservoirs would require large numbers of injection wells. To address this problem, we have explored polymer coatings as a surface engineering strategy to enhance transport of oxide nanoparticles in porous media. We report here on our studies of 2-line ferrihydrite NPs and the influence of poly (acrylic acid) (PAA) polymer coatings on the colloidal stability and transport in natural sand-packed column tests simulating flow in groundwater-saturated porous media. Measurements were also made of zeta potential, hydrodynamic diameter, and polymer adsorption and desorption properties. The coated NPs have a diameter range of 30-500 nm. We found that NP transport was improved by PAA coating and that the transport properties could be tuned by adjusting the polymer concentration. Our results demonstrate that a high stability of oxide particles and improved transport can be achieved in groundwater-saturated porous media by introducing negatively charged polyelectrolytes and optimizing polymer concentrations.
Original language | English (US) |
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Article number | 1705 |
Journal | Journal of Nanoparticle Research |
Volume | 15 |
Issue number | 7 |
DOIs | |
State | Published - Jul 1 2013 |
All Science Journal Classification (ASJC) codes
- General Chemistry
- Condensed Matter Physics
- Bioengineering
- Atomic and Molecular Physics, and Optics
- General Materials Science
- Modeling and Simulation
Keywords
- Adsorption
- Ferrihydrite
- Groundwater
- Iron oxide nanoparticles
- Polymer coating
- Stability
- Transport