Adsorption of Cu(II) ion by a novel hordein electrospun nanofiber modified by β-cyclodextrin

In this study, hordein and hordein/N,N'-methylene bisacrylamide (MBA) nanofiber membranes were prepared by electrospinning technique. Then the fabricated membranes were modified with beta-cyclodextrin (beta-CD) to remove heavy metal ions from aqueous solution. The prepared nanofiber membranes were characterized by ATR-FTIR, SEM and XRD. The diameters of the nanofibers were determined to be around 600-910 nm and beta-CD was successfully attached to the nanofiber membrane, which was confirmed by ATR-FTIR and XRD analysis. Cu(II) was selected as the model ion to investigate the heavy metal adsorption properties of the membranes. Adsorption capacities of the membranes increased with a higher initial pH, adsorption temperature and a longer adsorption time before reaching the saturation point. The adsorption isotherm results were described with the Langmuir model. It was found that additions of MBA and beta-CD at proper concentrations could significantly improve the adsorption capacities and the maximum adsorption of hordein, hordein/MBA, and hordein/MBA/beta-CD nanofiber membranes were 64.94, 81.97, and 88.50 mg/g, respectively. Furthermore, regeneration study showed that these hordein nanofiber membranes possessed reasonably good reusability. The novel functionalized hordein/MBA/beta-CD nanofiber membranes have great potential in the application of water treatment. (C) 2019 Elsevier B.V. All rights reserved.