Graphitic carbon nitride-reinforced polymer ionic liquid nanocomposite: a novel mixed-mode sorbent for microextraction in packed syringe

Abstract

ABSTRACT In this paper, a novel sorbent consisting of graphitic carbon nitride/polymer ionic liquid connected to halloysite nanotubes (g-C3N4-IL@HNT) was fabricated and used for benzene and phenol pollutant extraction from water samples. This mixed-mode sorbent contains multifunctional groups that allow interaction with several analytes, and because of its porosity, it can be embedded in a syringe device as the extractant without any filtration or centrifugation steps. A high-performance liquid chromatography-ultraviolet was used for the detection of analytes. The composition and morphology of the sorbent have been investigated by Fourier-transform infrared spectroscopy, scanning electron microscopy and energy-dispersive spectroscopy. In this work, parameters affecting the extraction methodology such as elution solvent and its volume, number of absorption cycles, number of solvent cycles, salt effect and matrix effect were investigated and optimised. Under the optimal conditions, a linear calibration curve was obtained in the range of 5–1000 μg L−1 (r 2 > 0.996) with detection limits (S/N = 3) of 0.5–1 μg L−1. The g-C3N4-IL@HNT showed proper characteristics for the extraction of benzene and phenol pollutant residues in the environmental water samples with recoveries between 71% and 104.8% and the relative standard deviation of 6.6–8.6% (intra-day) and 9–11% (inter-day).