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 nanomagnetic polyhedral oligomeric silsesquioxanes composite (Fe 3 O 4 @POSS), which can effectively adsorb and remove different environmental pollutants in aqueous solution. The obtained Fe 3 O 4 @POSS-SH possesses mesoporous architecture with a large specific surface area of 649.41 m 2 /g. Then a sulfonate-functionalized magnetic adsorbent (Fe 3 O 4 @POSS-SO 3 H) is derived through simple oxidization of the thiol moieties of Fe 3 O 4 @POSS-SH by H 2 O 2 . Fe 3 O 4 @POSS-SH or Fe 3 O 4 @POSS-SO 3 H 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 Fe 3 O 4 @POSS can be collected easily from water under a moderate magnetic field, facilitating the process of pollutants removal in water treatment.