Develop a rapid, potentially on-site method to screen firefighting wastewater for selected hazardous aromatic compounds.
Approach:
Method: Researchers combined thin-layer chromatography (TLC) separation with surface-enhanced Raman spectroscopy (SERS), using gold nanoparticles to enhance signals.
Test compounds: The method was tested on p-phenylenediamine, o-phenylenediamine, benzidine, and 4-chlorophenol.
Sample preparation: Wastewater was filtered before application to the TLC plate; separated compounds were analyzed using SERS and compound-specific calibration curves.
Key Findings:
TLC separated the four compounds in a standard mixture before SERS analysis.
In recovery experiments, the method identified and quantified added p-phenylenediamine, o-phenylenediamine, and 4-chlorophenol in firefighting wastewater; measured concentrations agreed with the amounts added.
Separating compounds before SERS helped reduce interference from overlapping Raman bands and other wastewater components.
Interpretation:
The study demonstrates TLC-SERS analysis of selected aromatic pollutants added to a real firefighting wastewater matrix.
Limitations:
The study does not establish performance across the wider range of chemicals that may occur in wastewater from different fires.
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