Preparation and characterization of deacetylated cellulose acetate/thermoplastic polyurethane nanofiber membranes modified with graphene oxide for methylene blue and Cr (VI) adsorption

Abstract

AbstractDeacetylated cellulose acetate/thermoplastic polyurethane@graphene oxide (DA/TPU@GO) nanofibrous membranes were prepared through the combination of electrospinning, deacetylation, and ultrasound‐assisted surface treatment techniques. The morphology, wettability, and mechanical properties of composite nanofiber membranes were studied via SEM, TEM, water contact angle measurements, and mechanical tests. Moreover, the adsorption capacity and mechanism of DA/TPU@GO nanofiber membranes for methylene blue and chromium (Cr (VI)) were analyzed. The introduction of active sites from GO led to a significant increase in the adsorption capacity of the DA/TPU@GO composite membranes compared with the DA/TPU composite nanofiber. The composite membrane featured adsorption capacities of 152.7 mg/g (25°C, pH 3) and 122.1 mg/g (25°C, pH 7) for Cr (VI) and methylene blue, respectively, which are higher than most other composite GO‐based adsorbents. The adsorption mechanism of the DA/TPU@GO composite membrane was consistent with the Langmuir isotherm and second‐order kinetic models. Therefore, the DA/TPU@GO composite nanofiber membrane served as an effective adsorbent with broad application prospects in the sewage treatment field owing to its excellent adsorption capacity.Highlights Nanofibers were prepared for the absorption of methylene blue (MB) and Cr (VI). Nanofibers exhibited adsorption capacities of 152.7 and 122.1 mg/g for Cr (VI) and MB. Adsorption mechanism follows Langmuir isotherm and second‐order kinetic models. Nanofibers have wide potential applications in sewage treatment.