Beta-Cyclodextrin Multi-Conjugated Magnetic Graphene Oxide as a Nano-Adsorbent for Methylene Blue Removal.

The composites of graphene oxide and magnetic nanoparticles multi-conjugated with beta-cyclodextrin (MNPs/GO-betaCD) were prepared by a facile route and their properties were investigated. First, poly(glycidyl methacrylate) was covalently wrapped onto the surface of magnetic nanoparticles (MNPs) by the reversible addition-fragmentation chain transfer polymerization. The mixture of modified MNPs and graphene oxide (GO) was then functionalized with beta-cyclodextrin to produce MNPs/GO-betaCD. The composites were characterized by FT-IR, XRD, TGA, SEM, and TEM. The MNPs/GO-betaCD owned a superparamagnetic character and showed remarkable methylene blue (MB) adsorption capacity from aqueous solution in comparison with GO. The adsorbent could be recycled and maintained about 64.4% of its initial adsorption capacity for MB after five regeneration cycles.