Nanofiltration membranes for wastewater treatment and biotechnological applications

Membrane separation technology is widely recognized as the most cost-effective and broad-spectrum employed technology for various applications. Nanofiltration membranes, which are the primary components of the nanofiltration process, have dominated the industry since it was launched in the 1980s. Antifouling, permeability, and the mechanical and thermal stability of nanofiltration membranes can be characterized by the membranes' physical and chemical morphology, which significantly impacts the segregation capability and operational expense in nanofiltration applications. Recently, significant progress has been made in the fabrication of nanofiltration membranes for various applications at the laboratory and commercial levels, for instance, in water and wastewater treatment, beverage industry, dairy, and pharmaceutical wastewater plants. Considering the scientific community's rapid interest in nanofiltration membranes, this chapter provides an insight into nanofiltration membrane fabrication and modification techniques employed to retain dissolved species such as dyes, heavy metals, pharmaceuticals, and personal care pollutants in various aqueous media. In addition, it presents the recent applications of nanofiltration membranes, particularly in wastewater and biotechnological applications. Finally, current barriers and research opportunities of nanofiltration membranes are reviewed, and future prospects are also discussed.