Guar gum coupled microscale ZVI for in situ treatment of CAHs: Continuous-flow column study

Autor(en)
Milica Velimirovic, Queenie Simons, Leen Bastiaens
Abstrakt

A column study was performed under in-situ conditions to evaluate to which extend the inactivation of the microscale zerovalent iron (mZVI) by guar gum occurs under continuous flow conditions. Five aquifer containing columns were set up under different conditions. Efficient removal of trichloroethene was observed for the column amended by mZVI. Stabilization of the mZVI with guar gum led to slightly reduced activity. More reduced reactivity was observed in the poisoned column containing guar gum stabilized mZVI. This confirms that soil microorganisms can degrade guar gum and that subsequent removal of the oligosaccharides by the groundwater flow (flushing effect) can reactivate the mZVI. After more than six months of continuous operation the columns were dismantled. DNA-based qPCR analysis revealed that mZVI does not significantly affect the bacterial community, while guar gum stabilized mZVI particles can even induce bacterial growth. Overall, this study suggests that the temporarily decreased mZVI reactivity due to guar gum, has a rather limited impact on the performance of in-situ reactive zones. The presence of guar gum slightly reduced the reactivity of iron, but also slowed down the iron corrosion rate which prolongs the life time of reactive zone.

Organisation(en)
Externe Organisation(en)
Flemish Institute for Technological Research (VITO)
Journal
Journal of Hazardous Materials
Band
265
Seiten
20-29
Anzahl der Seiten
10
ISSN
0304-3894
DOI
https://doi.org/10.1016/j.jhazmat.2013.11.020
Publikationsdatum
01-2014
Peer-reviewed
Ja
ÖFOS 2012
104023 Umweltchemie, 104002 Analytische Chemie, 105904 Umweltforschung, 210006 Nanotechnologie
Schlagwörter
ASJC Scopus Sachgebiete
Pollution, Waste Management and Disposal, Health, Toxicology and Mutagenesis, Environmental engineering, Environmental Chemistry
Link zum Portal
https://ucrisportal.univie.ac.at/de/publications/cc1a5293-076b-4414-99e8-6ef3622f6c27