Fabrication and properties of graphene oxide-embedded cellulose triacetate RO composite membrane via melting method

Abstract

Graphene oxide (GO) has attracted significant attention on account of its unique structure and superior performance, deriving a new research field for materials science. Herein, cellulose triacetate (CTA) flat-sheet RO composite membrane was fabricated with GO embedding in its layer via melting method, which exhibited higher permeate flux as compared to pristine CTA RO membrane. The morphologies and structural arrangements of the obtained composite membranes were analyzed by X-ray diffraction (XRD), Raman spectroscopy, Confocal scanning microscopy (CSM), and Scanning electron microscopy (SEM), respectively. It was found that thermogravimetric (TG) spectrograms revealed GO generating the degradation centres and changing degradation process with the increase addition of GO. Moreover, the mechanical property indicated that the incorporation of GO could contribute to the improvement of tensile strength from 10.2MPa to 23.1MPa because of the dominant interactions between CO groups from CTA and OH and COOH groups from GO. Finally, the RO membranes' performance showed that the permeate flux of membrane increased from 1.67L·m−2·h−1 to 4.74L·m−2·h−1 with the increasing GO content. However, the salt rejection compromised at the same time, perhaps due to the formation of channels which might offer the passageway of water accompanying by salt with the increasing GO content.