A platform for research: civil engineering, architecture and urbanism
A platform for research: civil engineering, architecture and urbanism
Coprecipitation of Heavy Metals in Calcium Carbonate from Coal Fly Ash Leachate
https://orcid.org/0000-0002-2576-3608
https://orcid.org/0000-0003-2418-795X
Water that comes into contact with coal fly ash contains toxic elements, including heavy metals. CO2 gas can be used for treatment by inducing precipitation of carbonates with alkaline earth metals, thereby coprecipitating toxic elements and neutralizing the pH. This process has the added benefit of sequestering CO2 and contributing to negative emissions of greenhouse gases. This investigation used a novel synchrotron-based approach with X-ray fluorescence nanospectroscopy at the NSLS-II HXN beamline. Multielement incorporation of As, Ba, Cr, Cu, and Zn into calcium carbonate was measured for a simulated fly ash leachate. We discovered that the extent of trace element incorporation was consistently higher than predicted by a thermodynamic model of solid solution coprecipitation, with incorporation of Cr being 3000 times more than predicted, and incorporation of Zn being 3 times more. Enhancement of trace element incorporation was correlated to the solubility of the endmembers (CaCrO4 > CaHAsO4 > BaCO3 > CuCO3 > ZnCO3). Iron inhibited trace element coprecipitation because the dominant process was surface adsorption. These results suggest that mineralization of heavy metals via coprecipitation in metastable carbonate phases is a more effective strategy for immobilizing toxic elements than solubility would suggest and is a promising environmental remediation strategy.
Toxic metals can be removed from water by coprecipitation with calcium carbonate even if aqueous concentrations are below solubility limits.
Coprecipitation of Heavy Metals in Calcium Carbonate from Coal Fly Ash Leachate
https://orcid.org/0000-0002-2576-3608
https://orcid.org/0000-0003-2418-795X
Water that comes into contact with coal fly ash contains toxic elements, including heavy metals. CO2 gas can be used for treatment by inducing precipitation of carbonates with alkaline earth metals, thereby coprecipitating toxic elements and neutralizing the pH. This process has the added benefit of sequestering CO2 and contributing to negative emissions of greenhouse gases. This investigation used a novel synchrotron-based approach with X-ray fluorescence nanospectroscopy at the NSLS-II HXN beamline. Multielement incorporation of As, Ba, Cr, Cu, and Zn into calcium carbonate was measured for a simulated fly ash leachate. We discovered that the extent of trace element incorporation was consistently higher than predicted by a thermodynamic model of solid solution coprecipitation, with incorporation of Cr being 3000 times more than predicted, and incorporation of Zn being 3 times more. Enhancement of trace element incorporation was correlated to the solubility of the endmembers (CaCrO4 > CaHAsO4 > BaCO3 > CuCO3 > ZnCO3). Iron inhibited trace element coprecipitation because the dominant process was surface adsorption. These results suggest that mineralization of heavy metals via coprecipitation in metastable carbonate phases is a more effective strategy for immobilizing toxic elements than solubility would suggest and is a promising environmental remediation strategy.
Toxic metals can be removed from water by coprecipitation with calcium carbonate even if aqueous concentrations are below solubility limits.
Coprecipitation of Heavy Metals in Calcium Carbonate from Coal Fly Ash Leachate
https://orcid.org/0000-0002-2576-3608
https://orcid.org/0000-0003-2418-795X
Water that comes into contact with coal fly ash contains toxic elements, including heavy metals. CO2 gas can be used for treatment by inducing precipitation of carbonates with alkaline earth metals, thereby coprecipitating toxic elements and neutralizing the pH. This process has the added benefit of sequestering CO2 and contributing to negative emissions of greenhouse gases. This investigation used a novel synchrotron-based approach with X-ray fluorescence nanospectroscopy at the NSLS-II HXN beamline. Multielement incorporation of As, Ba, Cr, Cu, and Zn into calcium carbonate was measured for a simulated fly ash leachate. We discovered that the extent of trace element incorporation was consistently higher than predicted by a thermodynamic model of solid solution coprecipitation, with incorporation of Cr being 3000 times more than predicted, and incorporation of Zn being 3 times more. Enhancement of trace element incorporation was correlated to the solubility of the endmembers (CaCrO4 > CaHAsO4 > BaCO3 > CuCO3 > ZnCO3). Iron inhibited trace element coprecipitation because the dominant process was surface adsorption. These results suggest that mineralization of heavy metals via coprecipitation in metastable carbonate phases is a more effective strategy for immobilizing toxic elements than solubility would suggest and is a promising environmental remediation strategy.
Toxic metals can be removed from water by coprecipitation with calcium carbonate even if aqueous concentrations are below solubility limits.
Coprecipitation of Heavy Metals in Calcium Carbonate from Coal Fly Ash Leachate
Hunter, Heather A. (author) / Ling, Florence T. (author) / Peters, Catherine A. (author)
ACS ES&T Water ; 1 ; 339-345
2021-02-12
Article (Journal)
Electronic Resource
English
Biosorption of Heavy Metals from Landfill Leachate onto Activated Sludge
| Online Contents | 2001
Carbonate coprecipitation synthesis of Sr- and Mg-doped LaGaO3
| British Library Online Contents | 2009
Removal of heavy metals from synthetic leachate using a biologically generated electric field
| Online Contents | 2007
Characterization of Heavy Metals from Coal Gangue
| Springer Verlag | 2020