Please use this identifier to cite or link to this item:
|Title:||Lab-scale simulation of the fate and transport of nano zero-valent iron in subsurface environments : aggregation, sedimentation, and contaminant desorption||Authors:||Lo, Irene M. C.
Mak, Mark S. H.
|Issue Date:||2012||Source:||Yin, K., Lo, I. M. C., Dong, H., Rao, P.,& Mak, M. S. H. (2012). Lab-scale simulation of the fate and transport of nano zero-valent iron in subsurface environments: Aggregation, sedimentation, and contaminant desorption. Journal of Hazardous Materials, 227-228, 118-125.||Series/Report no.:||Journal of hazardous materials||Abstract:||Heavy metal removal using nano zero-valent iron (NZVI) has drawn growing attention due to the ease of application and high removal efficiency. However, uncertainties regarding its fate and transport in subsurface environments have raised concerns that require further exploration. In this study, aggregation, sedimentation, and Cr/As desorption of three types of NZVIs were investigated under various conditions. It was found that the aggregation behavior of the NZVIs differed from one another in regard to reaction time and ionic strength, associated with the respective critical size for sedimentation. Sedimentation of NZVIs was positively related to the concentrations and average particle sizes. The sedimentation kinetics of NZVI followed two concomitant processes, i.e., (1) direct sedimentation of larger particles, and (2) initial aggregation and then sedimentation of smaller particles. When loaded with Cr/As, NZVIs tended to deposit faster, possibly due to the precipitation of Cr/As onto the nanoparticle surfaces resulting in larger particle sizes. Moreover, desorption of Cr/As from Cr/As loaded NZVIs was detected in the presence of typical groundwater ions, as well as natural organic matter, and poses a potential risk to the subsurface environment. The desorption of Cr was linearly related to the release of iron ions, while As desorption was mitigated when the immobilization of Cr increased.||URI:||https://hdl.handle.net/10356/97154
|ISSN:||0304-3894||DOI:||10.1016/j.jhazmat.2012.05.019||Rights:||© 2012 Elsevier B.V.||Fulltext Permission:||none||Fulltext Availability:||No Fulltext|
|Appears in Collections:||CEE Journal Articles|
Updated on Sep 1, 2020
Updated on Mar 6, 2021
Page view(s) 20466
Updated on May 10, 2021
Items in DR-NTU are protected by copyright, with all rights reserved, unless otherwise indicated.