Nanoparticles in reverse osmosis membranes for desalination: A state of the art review

The development of thin-film nanocomposite (TFNC) membranes utilizing nanoparticles present remarkable opportunity in the desalination industry. This review offers a comprehensive and in-depth analysis of TFNC membranes for reverse osmosis (RO) desalination by focusing on different issues existing in the RO process. Recent researches on nanoparticle incorporated TFNC membranes for application in water purification have been critically analyzed. The widely tested nanoparticles in these researches include carbon-based (carbon nanotube, graphene-oxide), metal and metal oxides-based (silver, copper, titanium dioxide, zinc oxide, alumina and metal-organic frameworks), and other nano-sized fillers like silica, halloysite, zeolite and cellulose-nano crystals based. These nanoparticles demonstrated pronounced effect in terms of water flux, salt rejection, chlorine resistance, and anti-fouling properties of TFNC membranes relative to the typical thin-film composite (TFC) membranes. Here, we also focus on the environmental impact, commercialization, and future scope of TFNC membranes. From the current review, it is evident that the nanomaterials possess exclusive properties, which can contribute to the advancement of high-tech nanocomposite membranes with improved capabilities for desalination. Despite all the developments, there still exist significant difficulties in the large-scale production of these membranes. Hence, additional studies in this field are required to produce TFNC membrane with increased performance for commercial application.