Preparation of the New Magnetic Nanoadsorbent Fe3O4@SiO2-yl-VP and Study on the Adsorption Properties of Hg (II) and Pb (II) in Water

This article reports the preparation of a novel functionalized magnetic nanoadsorbent through an addition reaction between Fe3O4 nanoparticles coated with allyl silica gel and 4-pyridinyl ethylene. A detailed characterization of Fe3O4@SiO2-yl-VP was conducted. Among them, in the infrared spectrum, we can easily see that the absorption peak of the C=C stretching vibration at 1660 cm−1 in the raw material disappears after the addition reaction, indicating the successful grafting of polymer on the surface of silica gel. The appearance of N element in the EDS spectrum also proves the successful completion of the addition reaction and the successful synthesis of Fe3O4@SiO2-yl-VP. At pH = 5 and pH = 7, it only takes half an hour for Fe3O4@SiO2-yl-VP to achieve maximum adsorption capacities of 85.06 and 73.78 mg/g for Hg (II) and Pb (II), respectively. The adsorption process conforms to the Langmuir model and the pseudo-first- and pseudo-second-order kinetic models and can be reused 11 times, demonstrating excellent reusability.