Sustainable Separations Using Organic Solvent Nanofiltration

Historically, industrialization is related to the increase in environmental pollution due to the industrial effluents produced. However, with the introduction of green industrial policy practices and sustainable developments in the regulations, industries are widely adopting cleaner and greener technologies in their processes. The nanofiltration process has been investigated and recognized as a sustainable separation platform for the past decades, due to its low energy requirement and applicability in various purification fields. In recent years, organic solvent nanofiltration (OSN) has been intensively studied in the field of pharmaceutical, food, petrochemical, and other fields that involve the use of organic solvents. However, as the production process of OSN membranes mostly involves the use of toxic chemicals, the sustainability of OSN as an alternative to distillation has been challenged. For OSN technology to be sustainable, various green alternatives and strategies for membrane fabrication have been recently introduced. These include the use of less toxic solvents for dissolving the polymers and for the polymerization process, the use of degradable and renewable sources of polymer, and reduction in solvent usage. Besides that, yield improvements in solvent recovery and separation processes have been studied through the use of different membrane cascade configurations.