Fuente: Journal of applied polymer Lugar: RESEARCH ARTICLE In this work, a magnetic PAA/ATP hydrogel adsorbent with a three-dimensional network structure was fabricated via inverse suspension polymerization, and its adsorption performance for the carbamate pesticide pirimicarb was systematically investigated. The hydrogel exhibited excellent adsorption capacity, superparamagnetic properties for easy recovery, and the adsorption process followed the Freundlich isotherm model and pseudo-second-order kinetic model, providing an effective strategy for the remediation of pesticide-contaminated wastewater.

ABSTRACT
Carbamate pesticides are crucial for enhancing crop production and ensuring food security, while their residues pose a significant risk of environmental contamination, the effective removal of carbamate pesticide residues is essential. Herein, a magnetic three-dimensional network structure hydrogel adsorbent was prepared by inverse suspension polymerization of hydrophilic vinyl monomers, modified with attapulgite and Fe3O4. This adsorbent had a strong adsorption capacity and was easy to recycle. The inverse phase suspension polymerization method has the advantages of a stable polymerization process, products need not be crushed, and it is easy to dry. In this paper, acrylic acid (AA) was used as the monomer, and a certain amount of activated attapulgite (ATP) was added. The magnetic PAA hydrogel was prepared by the inverse suspension phase polymerization method, and its structure and surface properties were examined using scanning electron microscopy (SEM), Brunauer–Emmet–Teller (BET), X-ray diffraction (XRD), and Fourier transform infrared (FTIR). On this basis, the magnetic PAA hydrogel's adsorption of carbamate pesticides was evaluated by isothermal and kinetic adsorption models. The adsorption behavior of pirimicarb on the magnetic PAA hydrogel adhered to the Freundlich model and pseudo-second-order kinetics, at an initial pirimicarb concentration of 20 mg·L−1, the adsorption reached 97.25% within 60 min. The manuscript could provide certain research ideas and technical supports for advanced treatment of pesticide-contaminated wastewater.