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Transforming contaminant ligands at water-solid interfaces via trivalent metal coordination
Qiandi Wang1, Qiongying Xu2, Wenzong Liu3
1CAS Key Laboratory of Environmental Biotechnology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, PR China; University of Chinese Academy of Sciences, Beijing, 100049, PR China.
Environment International
|September 16, 2024
Summary
Trivalent metal ions like aluminum (Al3+) significantly enhance the capture of pollutants such as tetracycline (TC) by humic acid (HA) through mediated coordination. This metal-driven interfacial binding is crucial for environmental remediation and wastewater treatment.
Area of Science:
- Environmental Chemistry
- Environmental Science
- Materials Science
Background:
- Contaminant behavior at water-solid interfaces is critical for environmental fate.
- Metal-contaminant interactions are key in remediation but interfacial aspects are underexplored.
Purpose of the Study:
- Investigate how trivalent metal ions influence pollutant migration to organic solid interfaces.
- Quantify the binding mechanisms and energies involved in metal-mediated contaminant capture.
Main Methods:
- Density Functional Theory (DFT) calculations to model HA-Al3+ binding.
- Experimental analysis of metal ion (Al3+) mediated binding of pollutants (TC) to humic acid (HA).
- Fluorescence spectroscopy to confirm Al3+-TC complex formation.
Main Results:
- Aluminum ions (Al3+) dramatically increase tetracycline (TC) binding to humic acid (HA) from 26.1% to 94.2%.
- Metal-mediated coordination significantly enhances binding energy from -5.71 kcal/mol to -84.89 kcal/mol.
- Excess free Al3+ can compete for TC binding, forming binary complexes.
Conclusions:
- Trivalent metal ions are pivotal in mediating pollutant capture at organic interfaces.
- Understanding interfacial metal-contaminant coordination advances environmental self-purification insights.
- Findings support the development of enhanced coagulation technologies for microscale pollutant removal.
Keywords:
CoagulationContaminant ligandsDensity functional theoryHumic acidInterfacial complexTrivalent metal ionsMore Related Videos
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