Poly(ether sulfone) Nanofibers Impregnated with β-Cyclodextrin for Increased Micropollutant Removal from Water

Abstract

Cyclodextrin–polymer composite electrospun nanofibers were developed for micropollutant (MP) removal from water. The fibers were fabricated by electrospinning of mixed poly­(ether sulfone) (PES) and β-cyclodextrin (CD) solutions under optimal conditions. The composite fibers were compared with bare PES nanofibers prepared by the same method. Scanning electron microscopy revealed that CD did not alter the fiber morphology, while the fiber capacity for MP uptake was enhanced by CD through the formation of inclusion complexes. The availability of CD on the fibers was confirmed by the emergence of visible luminescence due to the inclusion of a quantum cluster, Au25SBB18 (SBB = 4-(tert-butyl)­benzylmercaptan in thiolate form), in the cavities of CD exposed on fiber surfaces. The steroid hormone estradiol (E2) (100 ng/L) and pesticide chlorpyrifos (CP) (5 mg/L) were used as model pollutants in batch experiments designed to measure uptake potential. The nanofibers interact strongly with the model pollutants because of their high surface area and surface affinity. Increases of 20% in E2 uptake and 80% in CP uptake compared with bare PES nanofibers were observed. This behavior indicates promising applications of CD-containing materials for MP removal in water treatment and membrane technology.

Photo‐grafting of β‐cyclodextrin onto the polyethersulfone microfiltration‐membrane: Fast surface hydrophilicity improvement and continuous phthalate ester removal

“…The modification of the PES membranes or even polysulfone (PS) membrane has not been reported by the direct photografting. In the other reported works, the PES or PS membranes are mostly bulky modified which means firstly a primary polymer is chemically reacted with a β‐CD derivative and then β‐CD‐modified membrane is prepared via a phase inversion or an electrospinning method. In general, preparing membrane with bulky modifying method is not only a difficult and a time‐consuming preparation process but also, obtained membranes are not suitable candidates for practical applications due to their low fluxes.…”

“…They bonded β‐CD on the PES via making ester bond between hydroxyl groups in CD and sulfonate functional groups on the membrane surface . Schafe et al .developed a Cyclodextrin‐polymer‐composite electrospun nanofibers for application in removing micropollutant from water via electrospinning of mixed PES and β‐CD solutions . Based on our knowledge modification of PES membranes with β‐CD, by direct photografting methods, has not been reported yet.…”

Regeneration of β‐Cyclodextrin Based Membrane by Photodynamic Disulfide Exchange — Steroid Hormone Removal from Water

“…However, the stability of physically adsorbed β‐CD remains a concern due to its solubility in water. It is reported that nanofibers with physically impregnated β‐CD suffered a weight loss of 6.7 wt% after a hormone adsorption process of 96 h. [ 26 ] Although membranes loaded with crosslinked β‐CD prevented the leaching of β‐CD and achieved a high hormone removal efficiency, the regeneration of the membranes is to date not possible. [ 27 ] On the other hand, covalently attached β‐CD results in a permanent irreversible bonding of β‐CD onto the membrane surface.…”

“…[24] Because of this unique property, β-CD has been reported for removing a range of micropollutants from water and therefore serves as an ideal ligand for affinity adsorbents. [25][26][27][28][29][30] Commonly, β-CD is immobilized onto support membranes either by physical adsorption or covalent bonding. However, the stability of physically adsorbed β-CD remains a concern due to its solubility in water.…”

Environmentally Friendly Gelatin/β-Cyclodextrin Composite Fiber Adsorbents for the Efficient Removal of Dyes from Wastewater

“…Kadam et al used a composite polyacrylonitrile (PAN)/ β -CD nanofiber membrane to capture air pollutants, including aerosols and volatile organic compounds (VOCs), which showed an excellent air filtration performance [ 25 ]. Schafer et al prepared poly (ether sulfone) (PES) nanofibers with incorporated β -CD for micropollutant (MP) removal from water [ 26 ]. Zhao et al demonstrated a feasible method in the preparation of a water-insoluble sericin/ β -CD/poly (vinyl alcohol) composite nanofiber adsorbent by using electrospinning to remove the cationic dye methylene blue from aqueous solution [ 27 ].…”