Optimization of nano- and microiron transport through sand columns using polyelectrolyte mixtures

Bianca W. Hydutsky, Elizabeth J. Mack, Benjamin B. Beckerman, Joanna M. Skluzacek, Thomas E. Mallouk

Research output: Contribution to journalArticlepeer-review

146 Scopus citations


Sand-packed columns were used to study the transport of micro- and nanoiron particle suspensions modified with anionic polyelectrolytes. With microscale carbonyl iron powder (CIP), the profiles of initial and eluted particle diameters were compared with simulations based on classical filtration theory (CFT), using both the Tufenkji-Elimelech (TE) and Rajagopalan-Tien (RT) models. With particle size distributions that peaked in the submicron range, there was reasonable agreement between both models and the eluted distributions. With distributions that peaked in the 1.5 μm range, however, the eluted distributions were narrower and shifted to a smaller particle size than predicted by CFT. Apparent sticking coefficients depended on column length and flow rate, and the profile of retained iron in the columns did not follow the log-linear form expected from CFT. These observations could be rationalized in terms of the secondary energy minimum model recently proposed by Tufenkji and Elimelech (Langmuir 2005, 21, 841). For microiron, sticking coefficients correlated well with particle zeta potentials and polyacrylate (PAA) concentration. With nanoscale iron particles, there was no apparent correlation between filtration length and total electrolyte concentration. However, mixtures of PAA with poly(4-styrenesulfonate) and bentonite clay significantly enhanced nanoiron transport, possibly by affecting the aggregation of the particles.

Original languageEnglish (US)
Pages (from-to)6418-6424
Number of pages7
JournalEnvironmental Science and Technology
Issue number18
StatePublished - Sep 15 2007

All Science Journal Classification (ASJC) codes

  • General Chemistry
  • Environmental Chemistry


Dive into the research topics of 'Optimization of nano- and microiron transport through sand columns using polyelectrolyte mixtures'. Together they form a unique fingerprint.

Cite this