Efficient removal of cationic dyes from aqueous solution by polymer-modified magnetic nanoparticles

We explored the removal of cationic dyes – crystal violet, methylene blue and alkali blue 6B – from water solution by adsorption with magnetic nanoparticles (MNPs) modified with 3-aminopropyltriethoxysilane and copolymers of acrylic acid and crotonic acid. The noval magnetic nanoparticles was characterized by transmission electron microscopy, X-ray diffraction, infra-red spectra and thermogravimetric analysis. The cationic dyes could be quickly removed from water solution with high efficiency at pH 5–12. More significantly, the MNP showed high efficiency as a reusable adsorbent for fast and convenient removal of cationic dyes from water solution.

► Efficient removal of cationic dyes from aqueous solution by MNPs. ► Adsorption behavior for the cationic dyes in water solution. ► The cationic dyes were adsorbed from water solution in very short time. ► The adsorbent have high adsorption capacities and good performance in recycling.