New Poly(β-Cyclodextrin)/Poly(Vinyl Alcohol) Electrospun Sub-Micrometric Fibers and Their Potential Application for Wastewater Treatments

Abstract

Cyclodextrin (CD)-based polymers are known to efficiently form molecular inclusion complexes with various organic and inorganic guest compounds. In addition, they also have a great potential as metal complexes because deprotonated hydroxyls can strongly bind metal ions under alkaline conditions. The range of environmental conditions for polycyclodextrin/metal ion complexation can be extended by the polymerization of CDs with polyacids. This article describes the preparation and characterization of a new type of poly(β-cyclodextrin) (Poly-βCD) sub-micrometric fibers and explores their potential as metal ion sorbents. A water-soluble hyper-branched β-cyclodextrin polymer was blended with poly(vinyl alcohol) (PVA) and here used to improve the mechanical and morphological features of the fibers. Solutions with a different Poly-βCD/PVA ratio were electrospun, and the fibers were cross-linked by a post-spinning thermal treatment at 160 °C to ensure non-solubility in water. The fiber morphology was analyzed by scanning electron microscopy (SEM) before and after the curing process, and physical-chemical properties were studied by Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). The capability of the insoluble cyclodextrin-based fibers to remove heavy metals from wastewaters was investigated by testing the adsorption of Cu2+ and Cd2+ using inductively coupled plasma-optical emission spectroscopy (ICP-OES). The results suggest that the poly(β-cyclodextrin)/poly(vinyl alcohol) sub-micrometric fibers can complex metal ions and are especially effective Cu2+ sorbents, thus opening new perspectives to the development of fibers and membranes capable of removing both metal ions and organic pollutants.

Cyclodextrin Composite Nanofiber Membrane: Impact of the Crosslinker Type on Steroid Hormone Micropollutant Removal from Water

“…βCD-incorporated electrospun nanofibers are recently studied widely for the removal of heavy metals and micropollutants (see Table S4). ,− Therefore, CDs can be incorporated into nanofibers in order to remove and capture the MP. In the absence of crosslinking, this will result in leaching of the βCD .…”

Spherical Bi2WO6/Bi2S3/MoS2 n-p Heterojunction with Excellent Visible-Light Photocatalytic Reduction Cr(VI) Activity

“…With the rapid development of industrial production, the pollution of water and land resources by heavy metals is becoming increasingly serious [ 1 , 2 , 3 ]. Water-soluble, non-biodegradable hexavalent chromium Cr(VI), which easily penetrates through food chain enrichment, can induce cellular oxidative stress, leading to DNA damage, gene mutation, fetal malformation, and carcinogenesis, is one of the most dangerous heavy metals [ 4 , 5 ].…”

Recent Advancements in Cyclodextrin-Based Adsorbents for the Removal of Hazardous Pollutants from Waters

“…The ability of the insoluble CD-based fibers to eliminate heavy metals from wastewater was examined by analyzing the adsorption of Cu 2+ and Cd 2+ using ICP-OES. Poly-CD/PVA fibers exhibited an excellent response, especially towards the Cu(II), with a maximum adsorption capacity of 48.15 mg/g [101]. In another study, nano-sponges were fabricated through a complexation mechanism by cross-linking linecaps and CD with citric acid.…”