Nanomagnetic polyhedral oligomeric silsesquioxanes composite derived sulfur-containing adsorbents for effective elimination of hexavalent chromium and organic cationic dyes from water

This paper presents a facile strategy for designing magnetic adsorbents with versatile functions from nano-magnetic polyhedral oligomeric silsesquioxanes composite (Fe3O4@POSS), which can effectively adsorb and remove different environmental pollutants in aqueous solution. The obtained Fe3O4@POSS-SH possesses mesoporous architecture with a large specific surface area of 649.41 m(2)/g. Then a sulfonate-functionalized magnetic adsorbent (Fe3O4@POSS-SO3H) is derived through simple oxidization of the thiol moieties of Fe3O4@ POSS-SH by H2O2. Fe3O4@POSS-SH or Fe3O4@POSS-SO3H can respectively serve as an effective detergent for the elimination of Cr(VI) with high adsorption capacity of 185.19 mg/g, or cationic dye pollutants (such as neutral red, methylene blue and acriflavine with high adsorption capacity of 185.19, 175.44 and 128.21 mg/g, respectively). Notably, both sulfur-loaded Fe3O4@POSS can be collected easily from water under a moderate magnetic field, facilitating the process of pollutants removal in water treatment.