Determination of Forty Pollutants in Wastewater by Liquid–Liquid Extraction and Gas Chromatography–Mass Spectrometry

ABSTRACT

Liquid–liquid extraction with gas chromatography–mass spectrometry was used for the determination of 40 analytes in refinery wastewater. Liquid–liquid extraction was advantageous compared with microextraction procedures. The type and volume of the extraction solvent, extraction time, the type and volume of the organic modifier, and the sodium concentration were optimized. Under the optimum conditions, linear calibration curves were obtained for all analytes. The limits of the detection for the analytes were from 0.3 to 1.7 µg L⁻¹. The relative standard deviations were less than 10.0% in both intraday and interday measurements. Fortified recoveries at two levels were from 75.5 to 108.9%. The method was used to determine pollutants from treated refinery wastewater.

KEYWORDS:

• Gas chromatography–mass spectrometry (GC–MS)
• liquid–liquid extraction
• organic pollutants
• refinery wastewater