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Herein, a magnetic zirconium-based metal–organic framework nanocomposite was synthesized by a simple solvothermal method and used as an adsorbent for the removal of direct and acid dyes from aqueous solution. To enhance its adsorption performance, poly­(propyleneimine) dendrimer was used to functionalize the as-synthesized magnetic porous nanocomposite. The dendrimer-functionalized magnetic nanocomposite was characterized by field-emission scanning electron microscopy, X-ray diffraction, Fourier transform infrared spectroscopy, nitrogen adsorption/desorption isotherms, and vibration sample magnetometer. The obtained results revealed the successful synthesis and functionalization of the magnetic nanocomposite. The adsorbents exhibited good magnetic properties with high saturation magnetization and high specific surface area. The adsorption isotherms and kinetics of anionic dyes were described by the Freundlich and pseudo-second-order models, respectively. It was found that the kinetics of adsorption of both the investigated dyes by the dendrimer-functionalized magnetic composite is considerably faster than the magnetic composite under the same condition. The adsorption capacity of the dendrimer-functionalized magnetic composite for investigated direct and acid dyes was 173.7 and 122.5 mg/g, respectively, which was higher than those of the existing magnetic adsorbents. This work provides new insights into the synthesis and application of hybrid magnetic adsorbents with synergistic properties of nanoporous metal–organic frameworks and dendrimer with a large number of functional groups for the removal of organic dyes.

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This work attempted to fabricate superhydrophobic fabric via a simple immersion technique. Textile fabrics were coated with silica nanoparticles prepared from tetraethoxysilane (TEOS) to obtain sufficient roughness with hydrophobic surface chemistry. Then, the coated fabrics were treated with polydimethylsiloxane (PDMS) and aminopropyltriethoxysilane (APTES) to reduce the surface energy. The effects of the PDMS concentration on the surface morphology and superhydrophobicity of as-prepared fabric were investigated. The morphology and the composition of superhydrophobic fabric were characterized by scanning electron microscopy (SEM), energy dispersive X-ray (EDS), and Fourier transform infrared (FTIR) spectroscopy. The results revealed the formation of spherical silica nanoparticles with an average particle size of 250 nm throughout the fabric surface. The possible interactions between silica nanoparticles and APTES, as well as the fabrics, were elucidated. Investigating the hydrophobicity of fabrics via water contact angle (WCA) measurement showed that the treated fabric exhibits excellent water repellency with a water contact angle as high as 151° and a very low water sliding angle. It was also found that the treated fabric maintained most of its hydrophobicity against repeated washing, as the WCA of superhydrophobic fabrics decreased to 141° after 25 repeated washing cycles. The comfort properties of the obtained superhydrophobic fabrics in terms of air permeability and bending length did not reveal any significant changes.

Herein, an efficient adsorbent based on an activated carbon and metal−organic framework was developed for the adsorption of heavy metals from an aqueous solution. The structural and morphological characterizations of the Cr-MOF/ AC composite were evaluated by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM), exhibiting the formation of crystalline cubicshaped particles. The Cr-MOF/AC composite showed 3-fold higher specific surface area (2440 m 2 /g) than AC. The response surface methodology was employed to find the optimum adsorption conditions for the fast and efficient removal of lead and cobalt ions. The study of the kinetics of adsorption showed that the metal ions adsorption followed the pseudo-second-order model. The resultant composite was proved to be an excellent and highly efficient adsorbent with the adsorption capacity as high as 127 and 138 mg/g for lead and cobalt, respectively, under optimal conditions (pH = 5, an adsorption time of 40 min, adsorbent content of 25 mg, and metal ion concentration of 70 ppm). A further investigation on the reusability of adsorbent was also carried out, demonstrating the almost unchanged structure of the Cr-MOF/AC composite after five regeneration cycles. The Cr-MOF/AC composite exhibits a great potential for heavy metal adsorption and wastewater treatment.