Application of boehmite as a fiber coating for headspace solid-phase microextraction of chlorophenols from aqueous samples.

In this paper, the extraction of chlorophenols from water samples was carried out using high surface area boehmite nanoparticles as a sorbent. The surfactant-free process employed to make the nano-boehmite used in this work was simple, green, and efficient. The proposed approach was based on headspace solid-phase microextraction, followed by GC-ECD for the determination of analytes. In situ derivatization of analytes was performed with acetic anhydride in a basic medium. Various effective parameters, including the amount of derivatization reagent, ionic strength, desorption temperature and time, extraction temperature, equilibrium time, and extraction time were studied. Under optimal conditions, the linear dynamic range was 0.05-5.0 μg L -1 for 2,4-dichlorophenol and 2,6-dichlorophenol and 0.003-0.1 μg L -1 for 2,4,6-trichlorophenol. A low limit of detection (0.75 × 10 -3 -15 × 10 -3 μg L -1 ), and relative standard deviations for real samples (RSDs) <10% were obtained. The precision (as intra- and inter-day RSDs) was between 1.2 and 9.8%. In comparison to commercial fibers (CAR-PDMS, 85 μm), this fiber showed a greater extraction efficiency. Various water samples were subjected to extraction by the proposed method. The recoveries ranged from 90 to 110%.