Measuring the reactivity of commercially available zero-valent iron nanoparticles used for environmental remediation with iopromide

Autor(en)

Doris Schmid, Vesna Micic Batka, Susanne Laumann, Thilo Hofmann

Abstrakt

The high specific surface area and high reactivity of nanoscale zero-valent iron (nZVI) particles
have led to much research on their application to environmental remediation. The reactivity of
nZVI is affected by both the water chemistry and the properties of the particular type of nZVI
particle used.Wehave investigated the reactivity of three types of commercially available Nanofer
particles (from Nanoiron, s.r.o., Czech Republic) that are currently either used in, or proposed for
use in full scale environmental remediation projects. The performance of one of these, the
air-stable and thus easy-to-handle Nanofer Star particle, has not previously been reported.
Experiments were carried out first in batch shaking reactors in order to derive maximum
reactivity rates and provide a rapid estimate of the Nanofer particle's reactivity. The experiments
were performed under near-natural environmental conditions with respect to the pH value of
water and solute concentrations, and results were compared with those obtained using synthetic
water. Thereafter, the polyelectrolyte-coated Nanofer 25S particles (having the highest potential
for transport within porous media) were chosen for the experiments in column reactors, in order
to elucidate nanoparticle reactivity under a more field-site realistic setting.
Iopromide was rapidly dehalogenated by the investigated nZVI particles, following pseudo-firstorder
reaction kinetics that was independent of the experimental conditions. The specific surface
area normalized reaction rate constant (kSA) value in the batch reactors ranged between 0.12 and
0.53 L m−2 h−1; it was highest for the uncoated Nanofer 25 particles, followed by the polyacrylic
acid-coated Nanofer 25S and air-stable Nanofer Star particles. In the batch reactors all particles
were less reactive in natural water than in synthetic water. The kSA values derived from the
column reactor experiments were about 1000 times lower than those from the batch reactors,
ranging between 2.6 × 10−4 and 5.7 × 10−4 L m−2 h−1. Our results revealed that the easy-tohandle
and air-stable Nanofer Star particles are the least reactive of all the Nanofer products
tested. The reaction kinetics predicted by column experiments were more realistic than those
predicted by batch experiments and these should therefore be used when designing a full-scale
field application of nanomaterials for environmental remediation.

Organisation(en)

Externe Organisation(en)

Engineering Consultancy Tauw b.v.

Journal

Journal of Contaminant Hydrology

Band

181

Seiten

36-45

Anzahl der Seiten

10

ISSN

0169-7722

DOI

https://doi.org/10.1016/j.jconhyd.2015.01.006

Publikationsdatum

10-2015

Peer-reviewed

Ja

ÖFOS 2012

104023 Umweltchemie, 104002 Analytische Chemie, 105906 Umweltgeowissenschaften, 210006 Nanotechnologie

Schlagwörter

Link zum Portal

https://ucrisportal.univie.ac.at/de/publications/measuring-the-reactivity-of-commercially-available-zerovalent-iron-nanoparticles-used-for-environmental-remediation-with-iopromide(52e6edea-ae21-4fc1-8b95-57a2ca7b333e).html