Cyclodextrin‐Cross‐Linked Hydrogels for Adsorption and Photodegradation of Cationic Dyes in Aqueous Solution

Abstract

Possessing three‐dimensional porous structures and tunable mechanical strengths, cyclodextrin‐containing polymeric hydrogels are one of the most promising water‐based adsorbent materials due to their easy availability, simple chemical modification and environmental friendliness. In this work, two kinds of hydrogels were prepared via the copolymerization with acrylic acid and vinyl‐derivatized β‐cyclodextrins in water. These two gels have showed good adsorption performance towards cationic dyes through the noncovalent interactions with their anionic backbones and porous network. Meanwhile, pseudo‐second‐order model was selected to clarify the adsorption kinetics process. Moreover, nano‐scaled TiO2 was doped into these resultant cyclodextrins‐based hydrogels to achieve efficient degradation of dyes upon light irradiation. The obtained TiO2‐loaded hydrogels could exhibit improved adsorption performance and make the adsorbed dyes photo‐degraded with the decolorization rates above 95%. It can be envisioned that such cyclodextrin‐based soft materials may find applications in dye clearance and water treatment.

Magnetic Ti3C2 MXene Nanomaterials for Doxorubicin Adsorption from Aqueous Solutions: Kinetic, Isotherms, and Thermodynamic Studies

“…k 1 and k 2 are the rate constant of the pseudo-first-order models (min –1 ) and the pseudo-second-order models (mg μg –1 min –1 ), respectively. 28 , 30 …”

“…In order to study the adsorption kinetics of DOX on adsorbents, the experimental data were analyzed by pseudo-first-order and pseudo-second-order kinetics models. − The linear relationships are formed according to eqs and , where q e and q t are the amounts of DOX adsorbed at equilibrium and at time t (μg mg –1 ), respectively. k 1 and k 2 are the rate constant of the pseudo-first-order models (min –1 ) and the pseudo-second-order models (mg μg –1 min –1 ), respectively. , …”

“…k 1 and k 2 are the rate constant of the pseudo-first-order models (min −1 ) and the pseudo-second-order models (mg μg −1 min −1 ), respectively. 28,30 The kinetic parameters for DOX adsorption onto the Ti 3 C 2 @Fe 3 O 4 @β-CD are illustrated in Table 2. The correlation factors for the pseudo-first-order kinetic plot was less than 0.99, whereas the pseudo-second-order kinetic plot exhibited correlation factors of 0.9960 for DOX adsorption.…”

“…β-cyclodextrin (β-CD) is a kind of nontoxic cyclic oligosaccharides, and the most significant structure is hydrophilic exterior and hydrophobic interior cavity. , It is well known that β-CD can form stable host-guest inclusion complex with a variety of aromatic molecules into its hydrophobic cavity though host-guest interactions . However, the inherent solubility of β-CD hinders its practical application in a variety of areas .…”

Supramolecular hyperbranched polymer gels based on pillar[5]arene and their applications in removal of micropollutants from water

“…Meanwhile, the amounts of dyes and metal ions bound to the adsorbent were determined by eqn (2) as follows: 67 where q t (mg g −1 ) is the amount of dyes and metal ions adsorbed per gram of adsorbent at time t (min), c 0 (mg L −1 ) and c t (mg L −1 ) are the initial and residual concentrations of dyes and metal ions in the stock solutions and filtrates, and c A (g L −1 ) is the concentration of adsorbent SHPG powder or SHPG·H + powder.…”