Reactivity recovery of guar gum coupled mZVI by means of enzymatic breakdown and rinsing

Author(s)
M. Velimirovic, H. Chen, Q. Simons, L. Bastiaens
Abstract

Microscale zerovalent iron (mZVI) reduces chlorinated aliphatic hydrocarbons (CAHs) to harmless compounds, but the sedimentation of the mZVI particles in the injection fluid limits the injectability of the particles during field applications. In this study, mZVI particles in suspension were stabilized by green polymer guar gum, which had a positive impact on mZVI stability, but decreased the reactivity of the particles towards CAHs by 1 to 8 times. Guar gum (GG) was found to adsorb onto the mZVI surface, inhibiting contact between the chlorinated compounds and the reactive iron surface. Indications were found for intermolecular hydrogen bonding between mZVI and the guar gum. Subsequent addition of commercially available enzymes resulted in the cleavage of the polysaccharide guar gum into lower molecular fragments, but not in improved reactivity. The reactivity recovery of guar gum coupled mZVI was recovered after intensive rinsing of the iron particles, removing the guar gum fragments from the particles. Overall, this study shows that CAHs can be treated efficiently by guar gum stabilized mZVI after reactivation by means of enzymatic breakdown and rinsing.

Organisation(s)
External organisation(s)
Flemish Institute for Technological Research (VITO)
Journal
Journal of Contaminant Hydrology
Volume
142-143
Pages
1-10
No. of pages
10
ISSN
0169-7722
DOI
https://doi.org/10.1016/j.jconhyd.2012.09.003
Publication date
11-2012
Peer reviewed
Yes
Austrian Fields of Science 2012
210006 Nanotechnology, 104002 Analytical chemistry, 104023 Environmental chemistry, 105904 Environmental research
Portal url
https://ucrisportal.univie.ac.at/en/publications/f2a1e2bc-879a-47e0-84e6-1928f8da922c