Abstract
In-situ remediation of mercury at numerous contaminated sites worldwide is a challenging and costly endeavor due to the persistency of this contaminant. In this study, we evaluated eight commercially available sorbent media ranging from carbon-, clays- and silica-based materials (PBC– Biochar, eSorb – Sorbster, nsPAC – Powdered Activated Carbon, fsPAC – Powdered Activated Carbon with Mackinawite, F300 – Filtrasorb 300, Si-SH – Silica Thiol, eBind – RemBind, Q-Clay – Organoclay PM-199), for their effectiveness in sorbing mercury (Hg2+) and mercury complexed with dissolved organic matter (Hg-DOM). Under the chosen experimental conditions of this study, results showed that in the absence of DOM, the kinetic rates of Hg2+ sorption onto the evaluated sorbents were in the order of 0.31 min−1 (Si-SH) to 2.98 min−1 (nsPAC), whereas in the presence of DOM, the rates varied from 0.16 min−1 (F300) to 0.95 min−1 (nsPAC). The measured sorption capacity for Hg2+ in the absence of DOM varied from 3.02 mg/g (Q-Clay) to 35.15 mg/g (Si-SH), whereas in the presence of DOM, calculated partition coefficient (KD) ranged from 69.7 mL/g (Q-Clay) to 41,510 mL/g (Si-SH). Furthermore, kinetic data suggest liquid film diffusion was the rate-limiting steps governing mercury sorption onto the studied media. Overall, the obtained study parameters (kinetics/isotherm) are particularly important in informing robust engineering designs for deployment of the vast majority of evaluated sorbents. Thus, sorbent-based strategies offer viable solutions for cost-effective cleanup of mercury at industrially contaminated sites.
Original language | English |
---|---|
Article number | 113664 |
Journal | Journal of Environmental Chemical Engineering |
Volume | 12 |
Issue number | 5 |
DOIs | |
State | Published - Oct 2024 |
Funding
This work was funded by the U.S. Department of Energy under Cooperative Agreement DE-EM0000598 with Florida International University. This work was funded in part by the U.S. Department of Energy's (DOE) Oak Ridge Office of Environmental Management (ORO-EM) and United Cleanup Oak Ridge LLC (UCOR) to the Mercury Remediation Technology Development Program at Oak Ridge National Laboratory (ORNL). ORNL is managed by UT-Battelle, LLC, for the US DOE under Contract No. DE-AC05-00OR22725. The DOE will provide public access to the results of federally sponsored research in accordance with the DOE Public Access Plan (http://energy.gov/downloads/doe-public-access-plan). This work was funded by the U.S. Department of Energy under Cooperative Agreement DE-EM0000598 with Florida International University. This work was funded in part by the U.S. Department of Energy\u2019s (DOE) Oak Ridge Office of Environmental Management (ORO-EM) and United Cleanup Oak Ridge LLC (UCOR) to the Mercury Remediation Technology Development Program at Oak Ridge National Laboratory (ORNL). ORNL is managed by UT-Battelle, LLC, for the US DOE under Contract No. DE-AC05-00OR22725. The DOE will provide public access to the results of federally sponsored research in accordance with the DOE Public Access Plan ( http://energy.gov/downloads/doe-public-access-plan ). ORNL is managed by UT-Battelle, LLC under Contract No. DE-AC05-00OR22725 with DOE.
Keywords
- Adsorption
- Dissolved organic matter
- Kinetic
- Leaching
- Mercury
- Sorbent
- Stability