110th Anniversary: Selection of Cross-Linkers and Cross-Linking Procedures for the Fabrication of Solvent-Resistant Nanofiltration Membranes: A Review

Separation in organic mixtures is challenging but inevitable in many chemical and pharmaceutical processes. A membrane-based technique known as organic solvent nanofiltration (OSN) offers a sustainable and reliable solution due to its characteristics of low energy consumption and high efficiency. However, fabrication of a robust membrane that can maintain its separation performance in direct contact with organic solvents for a long period of time is challenging. The most common way to make a polymeric membrane resistant to organic solvents is to cross-link it with a three-dimensional network of polymer chains. However, selection of the right cross-linker for a particular polymer may not be very straightforward. Therefore, in this review, we aim to briefly introduce the common materials used for the fabrication of OSN membranes and demonstrate the state-of-art cross-linking procedures to improve the chemical stability of the membranes. This review may be helpful to researchers when selecting and modifying materials for the development of OSN membranes.