Contaminant immobilization through heterogeneous carbonate growth at mineral/water and mineral/microbe interfaces
EMSL Project ID
51915
Abstract
The presence of mineral surfaces and microorganisms significantly impacts the nature and composition of mineral phases formed in biogeochemical systems. Despite the importance of these heterogeneous reactions, predictions of the fate of biogeochemical systems relevant to DOE often rely solely on bulk thermodynamics due to a lack of robust theoretical tools that can predict heterogeneous mineral nucleation and growth. Moreover, the incorporation of contaminants in mineral phases formed heterogeneously at mineral/water and mineral/microbe interfaces significantly affects their reactivity, transport, and bioavailability and is therefore a critical aspect of terrestrial ecosystems. However, knowledge of the molecular-scale processes of contaminant immobilization in heterogeneous mineral phases remains limited. The long-term vision of this research is therefore to develop a quantitative understanding of contaminant immobilization in mineral precipitates at mineral/water and mineral/microbe interfaces to enable accurate predictions of the fate of metal contaminants in heterogeneous biogeochemical systems.Immobilization of divalent metal cations in carbonate precipitates formed at carbonate, silicate, and bacterial cell surfaces will be used as a model system due to the ubiquitous presence of carbonates in and major impact on soils, marine sediments, and suspended matter in fresh and sea waters. A combination of state-of-the-art experimental capabilities and molecular simulations will be deployed to overcome current limitations and quantify the surface chemical interactions that control contaminant incorporation into mineral precipitates formed heterogeneously. Specifically, this research will investigate: (1) the effects of substrate-coating chemical interactions on the incorporation of metal contaminants in carbonate coatings; and (3) any enhancement in metal contaminant incorporation afforded by the formation of an amorphous calcium carbonate intermediate during microbially-induced calcite (CaCO3) precipitation.
Project Details
Project type
Large-Scale EMSL Research
Start Date
2021-10-01
End Date
2023-09-30
Status
Closed
Released Data Link
Team
Principal Investigator
Co-Investigator(s)
Team Members
Related Publications
Sebastien N. Kerisit, Sebastian T. Mergelsberg, Micah P. Prange. 2021. "Ab Initio Molecular Dynamics Simulations of Amorphous Calcium Carbonate: Interpretation of Pair Distribution Function and X-ray Absorption Spectroscopy Data." Crystal Growth & Design 21 (4):2212-2221. https://dx.doi.org/10.1021/acs.cgd.0c01655
Trent R. Graham, Sebastien N. Kerisit, Sebastian T. Mergelsberg, Micah P. Prange, Shawn L. Riechers. 2021. "Effect of Cd on the Nucleation and Transformation of Amorphous Calcium Carbonate." Crystal Growth & Design 21 (6):3384-3393. https://doi.org/10.1021/acs.cgd.1c00169