Publication Details

Category Text Publication
Reference Category Journals
DOI 10.1016/j.scitotenv.2017.10.002
Title (Primary) Effect of field site hydrogeochemical conditions on the corrosion of milled zerovalent iron particles and their dechlorination efficiency
Author Velimirovic, M.; Auffan, M.; Carniato, L.; Micić Batka, V.; Schmid, D.; Wagner, S.; Borschneck, D.; Proux, O.; von der Kammer, F.; Hofmann, T.
Source Titel Science of the Total Environment
Year 2018
Department ANA
Volume 618
Page From 1619
Page To 1627
Language englisch
Supplements https://ars.els-cdn.com/content/image/1-s2.0-S0048969717326906-mmc1.doc
Keywords Milled zero valent iron; Hydrogeochemistry; Degradation; Apparent corrosion rate; Structural changes; Groundwater remediation
UFZ wide themes RU2;
Abstract Milled zerovalent iron (milled ZVI) particles have been recognized as a promising agent for groundwater remediation because of (1) their high reactivity with chlorinated aliphatic hydrocarbons, organochlorine pesticides, organic dyes, and a number of inorganic contaminants, and (2) a possible greater persistance than the more extensively investigated nanoscale zerovalent iron. We have used laboratory-scale batch degradation experiments to investigate the effect that hydrogeochemical conditions have on the corrosion of milled ZVI and on its ability to degrade trichloroethene (TCE). The observed pseudo first-order degradation rate constants indicated that the degradation of TCE by milled ZVI is affected by groundwater chemistry. The apparent corrosion rates of milled ZVI particles were of the same order of magnitude for hydrogeochemical conditions representative for two contaminated field sites (133–140 mmol kg− 1 day− 1, indicating a milled ZVI life-time of 128–135 days). Sulfate enhances milled ZVI reactivity by removing passivating iron oxides and hydroxides from the Fe0 surface, thus increasing the number of reactive sites available. The organic matter content of 1.69% in the aquifer material tends to suppress the formation of iron corrosion precipitates. Results from scanning electron microscopy, X-ray diffraction, and iron K-edge X-ray adsorption spectroscopy suggest that the corrosion mechanisms involve the partial dissolution of particles followed by the formation and surface precipitation of magnetite and/or maghemite. Numerical corrosion modeling revealed that fitting iron corrosion rates and hydrogen inhibitory terms to hydrogen and pH measurements in batch reactors can reduce the life-time of milled ZVI particles by a factor of 1.2 to 1.7.
Persistent UFZ Identifier https://www.ufz.de/index.php?en=20939&ufzPublicationIdentifier=20072
Velimirovic, M., Auffan, M., Carniato, L., Micić Batka, V., Schmid, D., Wagner, S., Borschneck, D., Proux, O., von der Kammer, F., Hofmann, T. (2018):
Effect of field site hydrogeochemical conditions on the corrosion of milled zerovalent iron particles and their dechlorination efficiency
Sci. Total Environ. 618 , 1619 - 1627 10.1016/j.scitotenv.2017.10.002