Oil-Water Separation of Electrospun Cellulose Triacetate Nanofiber Membranes Modified by Electrophoretically Deposited TiO₂/Graphene Oxide

Polymers (Basel). 2018 Jul 5;10(7):746. doi: 10.3390/polym10070746.

Abstract

Recycled waste industrial cellulose triacetate (TAC) film, which is one of the key materials in polarizers, was used to produce nanofiber membranes by electrospinning and synergistic assembly with graphene oxide (GO) and titanium dioxide (TiO₂) for oil-water separation. In this study, GO and TiO₂ coated by an electrophoretic deposition method introduced super hydrophilicity onto the recycled TAC (rTAC) membrane, with enhanced water permeability. The results indicate that when the outermost TiO₂ layer of an asymmetric composite fiber membrane is exposed to ultraviolet irradiation; the hydrophilicity of the hydrophilic layer is more effectively promoted. Moreover, this coating could efficiently repel oil, and demonstrated robust self-cleaning performance during the cycle test, with the aid of the photocatalytic properties of TiO₂. The rTAC membrane of networked hydrophobic fibers could also increase the speed of the filtrate flow and the water flux of the oil-water emulsion. The permeate carbon concentration in the water was analyzed using a total organic carbon analyzer. Incorporation of TiO₂/GO onto the rTAC membrane contributed greatly towards enhanced membrane hydrophilicity and antifouling performance. Therefore, the novel TiO₂/GO/rTAC asymmetric composite fiber has promise for applications in oil-water separation.

Keywords: cellulose triacetate; graphene oxide; oil-water separation; superhydrophilic; titanium dioxide.