skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Impacts of Aqueous Mn(II) on the Sorption of Zn(II) by Hexagonal Birnessite

Publication Date:
Research Org.:
Brookhaven National Laboratory (BNL), Upton, NY (United States)
Sponsoring Org.:
USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)
OSTI Identifier:
Report Number(s):
Journal ID: ISSN 0013-936X
DOE Contract Number:
Resource Type:
Journal Article
Resource Relation:
Journal Name: Environmental Science and Technology; Journal Volume: 49; Journal Issue: 8
Country of Publication:
United States

Citation Formats

Lefkowitz, J, and Elzinga, E. Impacts of Aqueous Mn(II) on the Sorption of Zn(II) by Hexagonal Birnessite. United States: N. p., 2015. Web. doi:10.1021/es506019j.
Lefkowitz, J, & Elzinga, E. Impacts of Aqueous Mn(II) on the Sorption of Zn(II) by Hexagonal Birnessite. United States. doi:10.1021/es506019j.
Lefkowitz, J, and Elzinga, E. 2015. "Impacts of Aqueous Mn(II) on the Sorption of Zn(II) by Hexagonal Birnessite". United States. doi:10.1021/es506019j.
title = {Impacts of Aqueous Mn(II) on the Sorption of Zn(II) by Hexagonal Birnessite},
author = {Lefkowitz, J and Elzinga, E},
abstractNote = {},
doi = {10.1021/es506019j},
journal = {Environmental Science and Technology},
number = 8,
volume = 49,
place = {United States},
year = 2015,
month = 3
  • We studied the impacts of aqueous Mn(II) (1 mM) on the sorption of Ni(II) (200 μM) by hexagonal birnessite (0.1 g L- 1) at pH 6.5 and 7.5 with batch experiments and XRD, ATR-FTIR and Ni K-edge EXAFS analyses. In the absence of Mn(II)aq, sorbed Ni(II) was coordinated predominantly as triple corner-sharing complexes at layer vacancies at both pH values. Introduction of Mn(II)aq into Ni(II)-birnessite suspensions at pH 6.5 caused Ni(II) desorption and led to the formation of edge-sharing Ni(II) complexes. This was attributed to competitive displacement of Ni(II) from layer vacancies by either Mn(II) or by Mn(III) formed throughmore » interfacial Mn(II)-Mn(IV) comproportionation, and/or incorporation of Ni(II) into the birnessite lattice promoted by Mn(II)-catalyzed recrystallization of the sorbent. Similar to Mn(II)aq, the presence of HEPES or MES caused the formation of edge-sharing Ni(II) sorption complexes in Ni(II)-birnessite suspensions, which was attributed to partial reduction of the sorbent by the buffers. At pH 7.5, interaction with aqueous Mn(II) caused reductive transformation of birnessite into secondary feitknechtite that incorporated Ni(II), enhancing removal of Ni(II) from solution. These results demonstrate that reductive alteration of phyllomanganates may significantly affect the speciation and solubility of Ni(II) in anoxic and suboxic environments.« less
  • No abstract prepared.
  • Birnessite minerals (layer-type MnO2), which bear both internal (cation vacancies) and external (particle edges) metal sorption sites, are important sinks of contaminants in soils and sediments. Although the particle edges of birnessite minerals often dominate the total reactive surface area, especially in the case of nanoscale crystallites, the metal sorption reactivity of birnessite particle edges remains elusive. In this study, we investigated the sorption selectivity of birnessite particle edges by combining Cd(II) and Pb(II) adsorption isotherms at pH 5.5 with surface structural characterization by differential pair distribution function (d-PDF) analysis. We compared the sorption reactivity of δ-MnO2 to that ofmore » the nanomineral, 2-line ferrihydrite, which exhibits only external surface sites. Our results show that, whereas Cd(II) and Pb(II) both bind to birnessite layer vacancies, only Pb(II) binds extensively to birnessite particle edges. For ferrihydrite, significant Pb(II) adsorption to external sites was observed (roughly 20 mol%), whereas Cd(II) sorption was negligible. These results are supported by bond valence calculations that show comparable degrees of saturation of oxygen atoms on birnessite and ferrihydrite particle edges. Therefore, we propose that the sorption selectivity of birnessite edges follows the same order of that reported previously for ferrihydrite: Ca(II) < Cd(II) < Ni(II) < Zn(II) < Cu(II) < Pb(II).« less