Abstract
Magnetite cryogel composites as macroporous crosslinked matrices have received wide attention and attract much interest in the water purification and desalination industry. They can be used to produce effective adsorbents with high adsorption rate, capacity and desorption for water pollutants. In this work, the incorporation of magnetite nanoparticles into cryogels by the in situ method is proposed to increase the dispersion of nanoparticles in the gel composites and to produce effective magnetic materials with high adsorption capacities. Ionic sodium-2-acrylamido-2-methylpropane sulfonate (Na-AMPS) monomer was selected to prepare cryogels as the homopolymer or copolymers with 2-hydroxyethyl methacrylate (HEMA) or N-vinyl pyrrolidone (VP) by the crosslinking polymerization technique in the frozen state. Magnetite nanoparticles were introduced into the cryogel by the in situ co-precipitation method after introducing iron cations into the cryogel networks. The surface morphologies, crystal structure, magnetite content, thermal stability and magnetic properties were determined for the cryogels and their magnetite composites. The magnetite cryogel composites show significantly enhanced methylene blue dye removal in short times with higher adsorption efficiencies and good regeneration to form an effective adsorbent for water treatment. (c) 2017 Society of Chemical Industry