KIT | KIT-Bibliothek | Impressum | Datenschutz

Immobilization of Cr(VI) by sulphate green rust and sulphidized nanoscale zerovalent iron in sand media: Batch and column studies

Digiacomo, F.; Tobler, D. J.; Held, T.; Neumann, T.

Abstract:
Chromate, Cr(VI), contamination in soil and groundwater poses serious threat to living organisms and environmental health worldwide. Sulphate green rust (GR$_{SO4}$), a naturally occurring mixed-valent iron layered double hydroxide has shown to be highly effective in the reduction of Cr(VI) to poorly soluble Cr(III), giving promise for its use as reactant for in situ remedial applications. However, little is known about its immobilization efficiency inside porous geological media, such as soils and sediments, where this reactant would ultimately be applied. In this study, we tested the removal of Cr(VI) by GR$_{SO4}$ in quartz sand fixed-bed column systems (diameter × length = 1.4 cm × 11 cm), under anoxic conditions. Cr(VI) removal efficiency (relative to the available reducing equivalents in the added GR$_{SO4}$) was determined by evaluating breakthrough curves performed at different inlet Cr(VI) concentrations (0.125–1 mM) which are representative of Cr(VI) concentrations found at contaminated sites, different flow rates (0.25–3 ml/min) and solution pH (4.5, 7 and 9.5). Results showed that (i) increasing Cr(VI) inlet concentration substantially decreased Cr(VI) removal efficiency of GR$_{SO4}$, (ii) flow rates had a lower impact on removal efficiencies, although values tended to be lower at higher flow rates, and (iii) Cr(VI) removal was enhanced at acidic pH conditions compared to neutral and alkaline conditions. ... mehr

Open Access Logo


Verlagsausgabe §
DOI: 10.5445/IR/1000124108
Veröffentlicht am 11.10.2020
Originalveröffentlichung
DOI: 10.1186/s12932-020-00073-9
Scopus
Zitationen: 1
Cover der Publikation
Zugehörige Institution(en) am KIT Institut für Angewandte Geowissenschaften (AGW)
Publikationstyp Zeitschriftenaufsatz
Publikationsjahr 2020
Sprache Englisch
Identifikator ISSN: 1467-4866
KITopen-ID: 1000124108
Erschienen in Geochemical transactions
Band 21
Heft 1
Seiten Art. Nr.: 8
Vorab online veröffentlicht am 14.08.2020
Schlagwörter Sulphate green rust, Sulphidized nZVI, Hexavalent chromium, Chromate, Packed bed columns, Reduction, Remediation
Nachgewiesen in Scopus
Web of Science
KIT – Die Forschungsuniversität in der Helmholtz-Gemeinschaft
KITopen Landing Page