Publication Details

Category Text Publication
Reference Category Journals
DOI 10.1016/j.jhazmat.2019.121450
Title (Primary) Effect of Fe-metabolizing bacteria and humic substances on magnetite nanoparticle reactivity towards arsenic and chromium
Author Sundman, A.; Vitzthum, A.-L.; Adaktylos-Surber, K.; Figueroa, A.I.; van der Laan, G.; Daus, B.; Kappler, A.; Byrne, J.M.
Source Titel Journal of Hazardous Materials
Year 2020
Department ANA
Volume 384
Page From art. 121450
Language englisch
Keywords Remediation; Pollution; Redox cycling; Microbes; Iron minerals
Abstract Magnetite is a magnetic, Fe(II)-Fe(III)-mineral formed through abiogenic and biogenic pathways. It constitutes an attractive material for remediation due to its reactivity, large surface-area-to-volume ratio when present as nanoparticles, and magnetic recoverability. Magnetite can be repeatedly microbially oxidized or reduced, but it is unclear how this influences the reactivity of magnetite towards toxic metal or metalloid contaminants. In this study, magnetite (both abiogenic and biogenic) was exposed to microbial Fe(II) oxidation and Fe(III) reduction, before reacted with hexavalent chromium (Cr(VI)) or pentavalent arsenic (As(V)). Results showed microbial reduction of both magnetite types improved the removal rate of Cr(VI) from solution, though surprisingly microbial Fe(II)-oxidation also showed enhanced reactivity towards Cr(VI) compared to un-treated magnetite. Synchrotron based analysis confirmed the formation of Cr(III) at the surface of the magnetite. Reactivity with As was less dramatic and showed un-treated material was able to remove As(V) from solution faster than microbially Fe(III)-reduced and Fe(II)-oxidized magnetite. The presence of humic substances was also shown to lead to a decreased reactivity of biogenic and abiogenic magnetite towards As(V) and Cr(VI). Our results imply that Fe-metabolizing bacteria influence the immobilization of contaminants and should be considered when evaluating remediation schemes, especially where Fe-metabolizing bacteria are active.
Persistent UFZ Identifier https://www.ufz.de/index.php?en=20939&ufzPublicationIdentifier=22854
Sundman, A., Vitzthum, A.-L., Adaktylos-Surber, K., Figueroa, A.I., van der Laan, G., Daus, B., Kappler, A., Byrne, J.M. (2020):
Effect of Fe-metabolizing bacteria and humic substances on magnetite nanoparticle reactivity towards arsenic and chromium
J. Hazard. Mater. 384 , art. 121450 10.1016/j.jhazmat.2019.121450