Supramolecular solvent combined with dispersive solid phase extraction based magnetic silicone surfactant activated charcoal adsorbent for extraction of phenolic compounds from industrial wastewater

Abstract

The present work describes a sensitive alternative procedure for the extraction and measurement of model analytes 2,4-dinitrophenol (2,4-DNP) and 2,4-dichlorophenol (2,4-DCP) from wastewater samples that uses supramolecular solvent (SUPRAS)-assisted non-ionic silicone surfactant-coated multifunctional magnetite activated charcoal (Fe3O4@AC-SS). In this study, decanoic acid reverse micelle-mediated SUPRAS and Fe3O4@AC-SS adsorbents was applied to magnetically separate the decanoic acid micelles containing the extracted phenolic compounds that were solubilized onto magnetic adsorbent-based surfactant. The Fe3O4@AC-SS adsorbent’s physical and surface properties were characterised using thermogravimetric analyser and Brunauer-Emmett-Teller surface analyser. The prepared Fe3O4@AC-SS was then applied as the adsorbent in the magnetic solid phase extraction (MSPE)-assisted SUPRAS technique to extract the phenolic compounds prior to high performance liquid chromatography diode array detection. Optimum extraction conditions were assessed with respect to adsorbent dosage, extraction time, SUPRAS volume, pH, ionic strength, sample volume, and desorption conditions (type, time, and volume). Under optimised conditions, good linearity with a coefficient of determination > 0.9991 and excellent limits of detection (0.0318–0.0384 μg/L) and quantification (0.1061–0.1281 μg/L) were achieved. Excellent recovery (85.30–116.85%) proved the suitability of the SUPRAS-MSPE technique for the extraction of phenolic compounds. No marked toxicity towards selected cell lines in the cell viability assay further confirmed that the extraction method and adsorbent were environmentally friendly and sensitive, and that the method has great potential for the extraction of phenolic compounds.