Effect of Additives during Interfacial Polymerization Reaction for Fabrication of Organic Solvent Nanofiltration (OSN) Membranes

Thin film composite (TFC) membranes is the dominant type of desalination in the field of membrane technology. Most of the TFC membranes are fabricated via interfacial polymerization (IP) technique. The ingenious chemistry of reacting acyl chlorides with diamines at the interface between two immiscible phases was first suggested by Cadotte back in the 1980s, and is still the main chemistry employed now. Researchers have made incremental improvements by incorporating various organic and inorganic additives. However, most of the TFC membrane literature are focused on improving the water desalination performance. Recently, the application spectrum of membrane technology has been expanding from the aqueous environment to harsh solvent environments, now commonly known as Organic Solvent Nanofiltration (OSN) technology. In this work, some of the main additives widely used in the desalination TFC membranes were applied to OSN TFC membranes. It was found that tributyl phosphate (TBP) can improve the solubility of diamine monomer in the organic phase, and sodium dodecyl sulfate (SDS) surfactant can effectively stabilize the IP reaction interface. Employing both TBP and SDS exhibited synergistic effect that improved the membrane permeance and rejection in solvent environments.

Automated summary

TFC membranes, fabricated through IP technique, are the dominant desalination type in membrane technology. Researchers have made incremental improvements to enhance the performance of TFC membranes. Recently, the application of additives, such as TBP and SDS, in Organic Solvent Nanofiltration technology has shown synergistic effects in improving membrane permeance and rejection.