Completely automated system for determining halogenated organic compounds by multisyringe flow injection analysis

Area of Science:

• Environmental Chemistry
• Analytical Chemistry
• Water Quality Analysis

Background:

• Halogenated organic compounds (HOCs) are significant environmental pollutants.
• Accurate determination of total adsorbable organic halogens (AOX) is crucial for water quality assessment.
• Existing methods for HOCs and AOX analysis can be time-consuming and labor-intensive.

Purpose of the Study:

• To develop the first fully automated flow injection methodology for HOCs determination.
• To enable expeditious and accurate in-line analysis of HOCs in water samples.
• To establish a reliable method for quantifying total adsorbable organic halogens (AOX).

Main Methods:

• A multisyringe flow injection setup was designed for automated sample handling.
• Solid-phase extraction (SPE) was employed for preconcentration and isolation of HOCs.
• UV light and a chemical oxidant were used to release bound halogens, followed by spectrophotometric determination.

Main Results:

• Optimized hydrodynamic and chemical parameters improved analytical performance.
• The method demonstrated a linear working range of 140-2000 µg L⁻¹ with a 5 mL sample volume.
• A limit of detection (LOD) of 100 µg L⁻¹ and a throughput of 9 samples h⁻¹ were achieved.
• Successful determination of AOX in well water and leachates, validated against a reference method.

Conclusions:

• The developed automated flow system provides an efficient and accurate approach for HOCs and AOX analysis.
• This methodology significantly advances in-line monitoring capabilities for environmental water analysis.
• The system holds considerable potential for routine environmental monitoring and regulatory compliance.