Recent Progresses in Preparation and Characterization of RO Membranes

Reverse osmosis (RO) is a water purifcation technology that uses a semipermeable membrane to remove ions, molecules, and larger particles for the production of drinking water. The frst RO membrane for seawater desalination, wastewater treatment and other applications were made of cellulose acetate. But, the polyamide thin-flm composite membrane that can tolerate wide pH ranges, higher temperatures, and harsh chemical environments is the most popular, currently. To further improve the membranes’ performances, the recent trend in polymer-based membrane research has been focused to investigate various types of nanocomposite membranes, in which nanosized fllers such as SMCNT, MWCNT, graphene, graphene oxide, silica, or zeolite are incorporated. However, there are many challenges to commercialize the application of these membranes. Nowadays, it is a norm to characterize membranes by the advanced characterization techniques such as Fourier transform infrared spectroscopy (ATR-FTIR), scanning electron microscope (SEM), atomic force microscopy (AFM), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), Raman spectroscopy and others for studying the physical and chemical properties of membranes and to co-relate those properties to the performances of the membranes. In this work, different aspects of RO membranes and proposed characterization methods, as well as recent progresses have been reviewed, comprehensively.