Properties and performances of polymer composite membranes correlated with monomer and polydopamine for flue gas dehydration by water vapor permeation

• Water vapor was separated by thin-film-composite membrane for flue gas dehydration.
• Membranes were characterized for the presence of thin film and coating layer.
• Effects of polydopamine coating time and monomer concentration were investigated.
• Conditions for preparation of membranes were optimized by their performances.

In this study, PES-based thin film composite (TFC) membranes were prepared by polydopamine (PDA) coating time and different monomer concentrations (i.e. m-phenylenediamine (MPD) and trimesoyl chloride (TMC) concentration). To investigate the influence of coating time by hydrophilic PDA material and monomer concentration, TFC membranes were classified into three different cases and tested under the same operating conditions. Various TFC membranes were characterized by using FE-SEM, ATR-FTIR, AFM and water contact angle to verify the modification on the surfaces. As a result, it is discovered that this membrane modification mainly improves the hydrophilicity on surface and the thickness of selective layer. Water vapor permeance and water vapor/N2 selectivity obtained here showed a close correlation to coating time and each monomer concentration. TFC membranes fabricated by interfacial polymerization (IP) show the better performances than other techniques for gas separation. Conditions for interfacial polymerization process to be efficiently utilized in permeation of water vapor were optimized to achieve the higher permeance and selectivity.

Figure optionsDownload as PowerPoint slide