Preparation of a New Polymerized Ionic Liquid-Modified Magnetic Nano Adsorbent for the Extraction and Preconcentration of Nitrate and Nitrite Anions from Environmental Water Samples

Abstract

In this research, a new type of poly ionic liquid-coated magnetic nanoparticle (MNPs@PIL) was designed and prepared via free radical polymerization. The as-synthesized MNPs were characterized using Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), thermo gravimetric analysis (TGA) and elemental analysis (EA). Then, they were successfully used as adsorbent in magnetic solid-phase extraction (MSPE) method for the extraction of nitrate and nitrite anions from water samples, and the analytes were finally determined by ion chromatography/conductivity detection. The effects of several experimental variables (including pH of sample solution, amount of the adsorbent, extraction and desorption time) were studied and the optimum values were determined. Under the optimum experimental conditions, detection limits (S/N = 3) of the proposed method for nitrate and nitrite were obtained as 0.2 and 0.133 µg L−1, respectively. The repeatability of the method, expressed as relative standard deviation (RSD), was lower than 5%. The proposed method was successfully applied for determination of nitrate and nitrite in real water samples.