Details

Autor(en) / Beteiligte

• Kim, Changwoo
• Lee, Seunghak

Titel

Effect of seepage velocity on the attachment efficiency of TiO2 nanoparticles in porous media

Ist Teil von

• Journal of hazardous materials, 2014-08, Vol.279, p.163-168

Ort / Verlag

Kidlington: Elsevier B.V

Erscheinungsjahr

2014

Quelle

MEDLINE

Beschreibungen/Notizen

• •α of TiO2 NPs in porous media increases with V in the lower range of V.•Hydrodynamic energy in the lower range of V is not enough to detach TiO2 NPs from sand.•A new relationship between α and V is needed to describe the subsurface transport of TiO2 NPs. Previously identified relationships between the attachment efficiency (α) and seepage velocity (US) of nanoparticles (NPs) were tested under simulated subsurface transport conditions, where the value of US is typically much less than the US on which they are based. This found an increase in the α value of TiO2 NPs with respect to US, which contradicts previous reports suggesting a constant value or decrease. By comparing the adhesion energy of the TiO2 NPs to sand and the hydrodynamic energy required to detach them, the increase of α with respect to US is found to be due to the difference in the magnitude of US considered; with 6.1E−05 to 1.3E−03ms−1 used in previous studies, whereas the current study uses a value in the range from 2.4E−06 to 4.9E−04ms−1. Only one of the previous models predicting α showed a similar increase of α with US, which was the result of it employing low velocities to examine the effects of organic matter. The current findings therefore suggest that previously determined relationships between α and US need to be further developed to incorporate more variables before they can be effectively used to describe or predict the subsurface transport of TiO2 NPs.