0506535 - ÚFCH JH 2020 RIV GB eng J - Journal Article
Touomo-Wouafo, M. - Donkeng Dazie, Joel - Btatkeu-K, B.D. - Tchatchueng, J. B. - Noubactep, Ch. - Ludvík, Jiří
Role of pre-corrosion of Fe-0 on its efficiency in remediation systems: An electrochemical study.
Chemosphere. Roč. 209, OCT 2018 (2018), s. 617-622. ISSN 0045-6535. E-ISSN 1879-1298
Institutional support: RVO:61388955
Keywords : zero-valent-iron * methylene-blue discoloration * long-term performance * metallic iron * granular iron * heavy-metals * removal * water * impact * sand * Zero-valent iron in water treatment * Role of pre-corrosion
OECD category: Electrochemistry (dry cells, batteries, fuel cells, corrosion metals, electrolysis)
Impact factor: 5.108, year: 2018
Method of publishing: Limited access

The duration of in-situ generation of iron corrosion products (FeCPs) prior the remediation process (so called ´´aging´´ of metallic iron (Fe-0)), was found as the key parameter affecting the efficiency of Fe-0 for water remediation. Batch experiments were performed in buffered solutions (pH 4.0, 4.7 and 5.5) and under oxic conditions (presence of dissolved oxygen) using Zn2+ as probe contaminant. The time-dependent (0-16 d) concentration changes of aqueous Fe2+ and Zn2+ were monitored using differential pulse polarography (DPP). During the time of pre-corrosion varying from 0 to 6 d, an ´´induction period´´ of the corrosion occurs in the first one 2 h when no Fe2+ ion is released in the solution. After this period, Fe2+ was identified in solution and its concentration progressively increases up to 6 h, then starts to decrease and after 6 d nearly disappears. Experiments with Zn2+ reveal that the most efficient Fe-0 remediation occurs after 6 h of pre-corrosion. This coherence thus proves that the presence, the amount and the age of FeCPs (´´degree´´ of corrosion) significantly impact the removal efficiency of Zn2+ in Fe-0/H2O systems. The present study severely refute the wording 'reactivity loss' and states that progress in designing sustainable Fe-0/H2O systems will not be achieved before the role of ´´active´´ FeCPs is clarified.
Permanent Link: http://hdl.handle.net/11104/0297763