Electrospun polyurethane nanofibers coated with polyaniline/polyvinyl alcohol as ultrafiltration membranes for the removal of ethinylestradiol hormone micropollutant from aqueous phase

Abstract

Estrogenic hormones at significant levels are a serious cause of fish femininity, breast and ovarian cancer as a consequence of hormonal imbalance. This study reports the fabrication of electrospun polyurethane (PU) nanofibers modified by coating with polyaniline/polyvinyl alcohol (PANI/PVA) to form filtration membranes for the enhanced removal of ethinylestradiol (EE2) estrogenic hormone. Structural and morphological character-ization was performed by FTIR, SEM and optical microscopy, while the detection and quantification of EE2 were analysed using HPLC. To understand the material characteristics, the feasibility of the results based on contact time and kinetics to determine the adsorption capacity coated PU nanofibers was further investigated. Findings demonstrated that EE2 best fitted pseudo-second-order kinetics. Furthermore, the adsorption process was opti-mised via response surface methodology using a central composite design model by varying parameters such as pH, temperature, the concentration of adsorbate, and adsorbent dosage to determine. It was found that the modified PU membranes had a maximum adsorption capacity of 2.11 mg/g and high removal percentage effi-ciency of ~82.20% for EE2. Adsorption mechanism and thermodynamics were also evaluated, and the results depicted the adsorption process of EE2 occurred via intraparticle diffusion and was exothermic in nature. Finally, a reusability study was done over six adsorption-desorption cycles to test the consistent effectiveness of the modified PU membrane, which remained above 80% removal capacity. Overall, the findings indicate that treated PU with stabilized PANI particles possess the potential to form an effective adsorbent for eradicating EE2 and other estrogenic hormones from the environment.