Nickel exchange between aqueous Ni(II) and deep-sea ferromanganese nodules and crusts

Tobias Hens, Joël Brugger, Barbara Etschmann, David Paterson, Helen E.A. Brand, Anne Whitworth, Andrew J. Frierdich

Research output: Contribution to journalArticleResearchpeer-review

Abstract

Deep-sea ferromanganese (Fe-Mn) nodules and crusts are rich in traditional and non-traditional metals with both current and emerging economic value. Mn(III,IV) oxides (e.g., phyllomanganates) are important host phases for these metals (e.g., Ni), which are structurally incorporated during nodule and Fe-Mn crust formation. Recrystallization of phyllomanganates can be catalyzed by aqueous Mn(II) (Mn(II)aq) during (bio)geochemical Mn redox cycling. The fate of structurally incorporated metals during such recrystallization of Mn(III,IV) oxides remains, however, poorly constrained. Here, we use a 62Ni isotope tracer to determine the exchangeability of dissolved Ni with structurally incorporated Ni in two deep-sea Fe-Mn nodules and one Fe-Mn crust. Ni exchange between solid and solution was investigated during reactions in 1 mM Mn(II)aq and in Mn(II)-free solutions under variable pH conditions (pH 5.5 and 7.5) over time. Sample characterization shows that all samples are of hydrogenetic or mixed hydrogenetic-diagenetic origin and Ni is preferentially associated with the phyllomanganates. Our Ni exchange experiments reveal that in some samples up to 25% of incorporated Ni is exchangeable with the fluid after 14 days. The prevalent reaction pathways exhibit pH-dependent behavior during phyllomanganate recrystallization and differ between sample types, with Mn(II)aq enhancing Ni exchange in the Fe-Mn crust-fluid system and Ni exchange being independent of Mn(II)aq concentrations in the Fe-Mn nodule-fluid systems. The exchangeability of structurally-incorporated Ni in Fe-Mn nodules and crusts indicates a labile behavior that potentially makes it available for biogeochemical processes in the marine environment.

Original languageEnglish
Article number119276
Number of pages13
JournalChemical Geology
Volume528
DOIs
Publication statusPublished - 5 Dec 2019

Keywords

  • Ferromanganese nodules
  • Mn (oxyhydr)oxides
  • Ni isotopes
  • Polymetallic crusts
  • Recrystallization
  • Redox cycling

Cite this

Hens, Tobias ; Brugger, Joël ; Etschmann, Barbara ; Paterson, David ; Brand, Helen E.A. ; Whitworth, Anne ; Frierdich, Andrew J. / Nickel exchange between aqueous Ni(II) and deep-sea ferromanganese nodules and crusts. In: Chemical Geology. 2019 ; Vol. 528.
@article{118e244f7a82417d915ac94c74850238,
title = "Nickel exchange between aqueous Ni(II) and deep-sea ferromanganese nodules and crusts",
abstract = "Deep-sea ferromanganese (Fe-Mn) nodules and crusts are rich in traditional and non-traditional metals with both current and emerging economic value. Mn(III,IV) oxides (e.g., phyllomanganates) are important host phases for these metals (e.g., Ni), which are structurally incorporated during nodule and Fe-Mn crust formation. Recrystallization of phyllomanganates can be catalyzed by aqueous Mn(II) (Mn(II)aq) during (bio)geochemical Mn redox cycling. The fate of structurally incorporated metals during such recrystallization of Mn(III,IV) oxides remains, however, poorly constrained. Here, we use a 62Ni isotope tracer to determine the exchangeability of dissolved Ni with structurally incorporated Ni in two deep-sea Fe-Mn nodules and one Fe-Mn crust. Ni exchange between solid and solution was investigated during reactions in 1 mM Mn(II)aq and in Mn(II)-free solutions under variable pH conditions (pH 5.5 and 7.5) over time. Sample characterization shows that all samples are of hydrogenetic or mixed hydrogenetic-diagenetic origin and Ni is preferentially associated with the phyllomanganates. Our Ni exchange experiments reveal that in some samples up to 25{\%} of incorporated Ni is exchangeable with the fluid after 14 days. The prevalent reaction pathways exhibit pH-dependent behavior during phyllomanganate recrystallization and differ between sample types, with Mn(II)aq enhancing Ni exchange in the Fe-Mn crust-fluid system and Ni exchange being independent of Mn(II)aq concentrations in the Fe-Mn nodule-fluid systems. The exchangeability of structurally-incorporated Ni in Fe-Mn nodules and crusts indicates a labile behavior that potentially makes it available for biogeochemical processes in the marine environment.",
keywords = "Ferromanganese nodules, Mn (oxyhydr)oxides, Ni isotopes, Polymetallic crusts, Recrystallization, Redox cycling",
author = "Tobias Hens and Jo{\"e}l Brugger and Barbara Etschmann and David Paterson and Brand, {Helen E.A.} and Anne Whitworth and Frierdich, {Andrew J.}",
year = "2019",
month = "12",
day = "5",
doi = "10.1016/j.chemgeo.2019.119276",
language = "English",
volume = "528",
journal = "Chemical Geology",
issn = "0009-2541",
publisher = "Elsevier",

}

Nickel exchange between aqueous Ni(II) and deep-sea ferromanganese nodules and crusts. / Hens, Tobias; Brugger, Joël; Etschmann, Barbara; Paterson, David; Brand, Helen E.A.; Whitworth, Anne; Frierdich, Andrew J.

In: Chemical Geology, Vol. 528, 119276, 05.12.2019.

Research output: Contribution to journalArticleResearchpeer-review

TY - JOUR

T1 - Nickel exchange between aqueous Ni(II) and deep-sea ferromanganese nodules and crusts

AU - Hens, Tobias

AU - Brugger, Joël

AU - Etschmann, Barbara

AU - Paterson, David

AU - Brand, Helen E.A.

AU - Whitworth, Anne

AU - Frierdich, Andrew J.

PY - 2019/12/5

Y1 - 2019/12/5

N2 - Deep-sea ferromanganese (Fe-Mn) nodules and crusts are rich in traditional and non-traditional metals with both current and emerging economic value. Mn(III,IV) oxides (e.g., phyllomanganates) are important host phases for these metals (e.g., Ni), which are structurally incorporated during nodule and Fe-Mn crust formation. Recrystallization of phyllomanganates can be catalyzed by aqueous Mn(II) (Mn(II)aq) during (bio)geochemical Mn redox cycling. The fate of structurally incorporated metals during such recrystallization of Mn(III,IV) oxides remains, however, poorly constrained. Here, we use a 62Ni isotope tracer to determine the exchangeability of dissolved Ni with structurally incorporated Ni in two deep-sea Fe-Mn nodules and one Fe-Mn crust. Ni exchange between solid and solution was investigated during reactions in 1 mM Mn(II)aq and in Mn(II)-free solutions under variable pH conditions (pH 5.5 and 7.5) over time. Sample characterization shows that all samples are of hydrogenetic or mixed hydrogenetic-diagenetic origin and Ni is preferentially associated with the phyllomanganates. Our Ni exchange experiments reveal that in some samples up to 25% of incorporated Ni is exchangeable with the fluid after 14 days. The prevalent reaction pathways exhibit pH-dependent behavior during phyllomanganate recrystallization and differ between sample types, with Mn(II)aq enhancing Ni exchange in the Fe-Mn crust-fluid system and Ni exchange being independent of Mn(II)aq concentrations in the Fe-Mn nodule-fluid systems. The exchangeability of structurally-incorporated Ni in Fe-Mn nodules and crusts indicates a labile behavior that potentially makes it available for biogeochemical processes in the marine environment.

AB - Deep-sea ferromanganese (Fe-Mn) nodules and crusts are rich in traditional and non-traditional metals with both current and emerging economic value. Mn(III,IV) oxides (e.g., phyllomanganates) are important host phases for these metals (e.g., Ni), which are structurally incorporated during nodule and Fe-Mn crust formation. Recrystallization of phyllomanganates can be catalyzed by aqueous Mn(II) (Mn(II)aq) during (bio)geochemical Mn redox cycling. The fate of structurally incorporated metals during such recrystallization of Mn(III,IV) oxides remains, however, poorly constrained. Here, we use a 62Ni isotope tracer to determine the exchangeability of dissolved Ni with structurally incorporated Ni in two deep-sea Fe-Mn nodules and one Fe-Mn crust. Ni exchange between solid and solution was investigated during reactions in 1 mM Mn(II)aq and in Mn(II)-free solutions under variable pH conditions (pH 5.5 and 7.5) over time. Sample characterization shows that all samples are of hydrogenetic or mixed hydrogenetic-diagenetic origin and Ni is preferentially associated with the phyllomanganates. Our Ni exchange experiments reveal that in some samples up to 25% of incorporated Ni is exchangeable with the fluid after 14 days. The prevalent reaction pathways exhibit pH-dependent behavior during phyllomanganate recrystallization and differ between sample types, with Mn(II)aq enhancing Ni exchange in the Fe-Mn crust-fluid system and Ni exchange being independent of Mn(II)aq concentrations in the Fe-Mn nodule-fluid systems. The exchangeability of structurally-incorporated Ni in Fe-Mn nodules and crusts indicates a labile behavior that potentially makes it available for biogeochemical processes in the marine environment.

KW - Ferromanganese nodules

KW - Mn (oxyhydr)oxides

KW - Ni isotopes

KW - Polymetallic crusts

KW - Recrystallization

KW - Redox cycling

UR - http://www.scopus.com/inward/record.url?scp=85071078202&partnerID=8YFLogxK

U2 - 10.1016/j.chemgeo.2019.119276

DO - 10.1016/j.chemgeo.2019.119276

M3 - Article

VL - 528

JO - Chemical Geology

JF - Chemical Geology

SN - 0009-2541

M1 - 119276

ER -