Cationic-modified cyclodextrin nanosphere/anionic polymer as flocculation/sorption systems.

Huining Xiao; Norlito Cezar

doi:10.1016/j.jcis.2004.09.008

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Cationic-modified cyclodextrin nanosphere/anionic polymer as flocculation/sorption systems.

Huining Xiao·Norlito Cezar

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Abstract

Simultaneous removal of dissolved and colloidal substances has been a challenging task. The cationic-modified beta-cyclodextrin nanospheres synthesized in this work, in conjunction with a water-soluble polyacrylamide-based anionic polymer, potentially provide a novel approach to address the problem. The cyclodextrin was rendered cationic using (2,3-epoxypropyl)trimethylammonium chloride as a reagent. The cationicity of the modified cyclodextrin and the reaction between cyclodextrin and the reagent were characterized by electrophoresis measurement, polyelectrolyte titration, and NMR. As a dual-component flocculation system, the cationic cyclodextrin/anionic polymer significantly induced clay flocculation, lowering the relative turbidity of the clay suspension over a wide pH range. Meanwhile, as a nanospherical absorbent, the modified cyclodextrins exhibited strong affinity toward aromatic compounds via inclusion complex formation in the hydrophobic cavities, which was monitored by UV spectroscopy. These systems facilitated the simultaneous removal of dissolved and colloidal substances, which was unachievable previously. In addition, the interaction between anionic polymers and the clay particles pretreated with cationic cyclodextrin was investigated in order to reveal the flocculation mechanism.

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Acrylic Resins Adsorption Anions Cations Colloids Epoxy Compounds Flocculation Hydrogen-Ion Concentration Molecular Structure Nanostructures Osmolar Concentration Particle Size Polymers Quaternary Ammonium Compounds Surface Properties Time Factors beta-Cyclodextrins Polyacrylamides Journal Article

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Huining Xiao, Norlito Cezar. 2005-03-15. Cationic-modified cyclodextrin nanosphere/anionic polymer as flocculation/sorption systems.. https://doi.org/10.1016/j.jcis.2004.09.008

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