Application of a sorbent based on graphene oxide modified with magnetic nanoparticles for the separation of organic contaminants in wastewater.

Abstract

These advantages have been further extended through the functionalization of GO with magnetic nanoparticles (MNPs), resulting in sorbents with enhanced stability and durability. Furthermore, the easy separation of GO-MNP-based sorbents from aquatic solutions through magnetic field application facilitates sorbent reusability, thus minimizing economic cost and environmental impact. In this study, the adsorption capacity of a novel GO-MNP sorbent material, patented as M@GO [2], for the removal of 30 OCs from wastewater was investigated using liquid chromatography coupled with high-resolution mass spectrometry (LC-Orbitrap-MS) for sample analysis. Adsorption optimization comprising solution pH, adsorption method, and contact time were evaluated. 77% of the OCs showed adsorption results between 70 and 100% with relative standard deviations (RSDs) less than 20% using ultrasound-assisted extraction (UAE) for 5min at the typical pH of wastewater effluents (7.5–8). Given the successful results in terms of specificity for OCs and applicability in wastewater decontamination, a magnetic solid-phase extraction (MSPE) method was proposed to investigate sorbent reusability. Factors including extraction time, elution solvent, and solvent pH modifiers were examined. The best recovery results were observed employing 1mL of MeOH with 1% acetic acid (v/v) using UAE for 2min, achieving acceptable recovery rates (70–120%, RSD<20%) for the 40% of the OCs.