Novel TiO2/GO-Al2O3 Hollow Fiber Nanofiltration Membrane for Desalination and Lignin Recovery
Xuelong Zhuang, Edoardo Magnone, Min Chang Shin, Jeong In Lee, Jae Yeon Hwang, Young Chan Choi, Jung Hoon Park
Abstract
Due to its greater physical–chemical stability, ceramic nanofiltration (NF) membranes were used in a number of industrial applications. In this study, a novel NF membrane was prepared by co-depositing a titanium dioxide (TiO2) and graphene oxide (GO) composite layer directly onto a porous α-Al2O3 hollow fiber (HF) support. An 8 µm-thick TiO2/GO layer was deposited to the surface of α-Al2O3 HF support by vacuum deposition method to produce advanced TiO2/GO-Al2O3 HF NF membrane. Scanning electron microscope (SEM) micrographs, energy dispersive spectrometer (EDS), X-ray powder diffraction (XRD), thermogravimetric analyzer (TGA), porosity, 3-point bending strength, zeta potential analysis, and hydrophilic properties by water contact angle are used for TiO2/GO-Al2O3 HF NF membrane characterization. The results show that the developed membrane’s MWCO ranged from 600 to 800 Da. The water flux, rejection of lignin, and sodium ions were 5.6 L/m2 h·bar, ~92.1%, and ~5.5%, respectively. In a five-day NF process, the TiO2/GO-Al2O3 HF NF membrane exhibits good lignin permeation stability of about 14.5 L/m2 h.