Synthesis and Characterization of Halloysite–Cyclodextrin Nanosponges for Enhanced Dyes Adsorption

Abstract

Inorganic−organic nanosponge hybrids based on halloysite clay and organic cyclodextrin derivatives (HNT-CDs) were developed by means of microwave irradiations in solvent-free conditions. The HNT-CDs nanomaterials characterized by FT-IR, TGA, BET, TEM, SEM, DLS, and ζ-potential have showed a hyper-reticulated network which possesses both HNT and cyclodextrin peculiarities. The new HNT-CDs nanosponge hybrids were employed as nanoadsorbents, first choosing Rhodamine B as the dye model, and furthermore for the removal of some cationic and anionic dyes, under different pH values (1.0, 4.54, and 7.4). The collected results showed that the pH solution as well as the electrostatic interactions affect the adsorption process. Factors controlling the adsorption process were discussed. The experimental adsorption equilibrium and kinetic data were best described by the Freundlich isotherm model. Excellent adsorption efficiency for cationic dyes were observed with respect to anionic ones. The results suggest that HNT-CDs nanosponge hybrids are a good nanoadsorbent for selective adsorption of cationic dyes with respect to the anionic ones from aqueous solutions.

High‐flux PVDF membrane incorporated with β‐cyclodextrin modified halloysite nanotubes for dye rejection and Cu (II) removal from water

“…However, a higher weight loss was observed for β‐CD‐HNTs between approximately 250 and 400°C compared with the unmodified HNTs, which was attributed to the decomposition of functional groups in β‐CD‐HNTs. Overall, the total weight loss of HNTs was 14.5%, whereas the total weight loss of β‐CD‐HNTs reached 44.1% …”

“…Overall, the total weight loss of HNTs was 14.5%, whereas the total weight loss of β-CD-HNTs reached 44.1%. 37 The morphologies of raw HNTs (a) and β-CD-HNTs (b) were observed by TEM shown in Figure 5. As we know, HNTs belong to a hollow tubular structure with 2 open ends, which provides some hydrophilic channels for water permeation.…”

Two in One: Modified Polyurethane Foams by Dip‐Coating of Halloysite Nanotubes with Acceptable Flame Retardancy and Absorbency

“…Adsorption ability of HNTs‐PUF is universal since HNTs are capable of adsorbing dyes and metal ions. For example, HNTs are capable of adsorbing dyes such as Rhodamine B, methylene blue, methyl violet, methyl orange, and neutral red in aqueous solution . The HNTs‐PUF has a high porosity, which is also a key factor to possess the high adsorption ability to MB in an aqueous solution.…”

“…For example, HNTs are capable of adsorbing dyes such as Rhodamine B, methylene blue, methyl violet, methyl orange, and neutral red in aqueous solution. [60][61][62][63] The HNTs-PUF has a high porosity, which is also a key factor to possess the high adsorption ability to MB in an aqueous solution. This suggests that HNTs-PUF may be used in wastewater treatment applications, showing potential value for environmental-restoration.…”

Palladium nanoparticles immobilized on cyclodextrin‐decorated halloysite nanotubes: Efficient heterogeneous catalyst for promoting copper‐ and ligand‐free Sonogashira reaction in water–ethanol mixture

“…However, a monolayer of H 2 O molecules separates the unit layers in HNTs . High mechanical strength, large surface area and large internal and outer diameters (10–100 and 30–190 nm, respectively) render HNTs a promising candidate for developing (photo)catalysts, drug carriers, polymeric matrices and state‐of‐the‐art materials with the utility for separation, waste treatment and electrical applications …”