Fabrication of high performance and durable forward osmosis membranes using mussel-inspired polydopamine-modified polyethylene supports

• Published in: Journal of membrane science Vol. 584; pp. 89 - 99
• Main Authors: Kwon, Soon Jin, Park, Sang-Hee, Shin, Min Gyu, Park, Min Sang, Park, Kiho, Hong, Seungkwan, Park, Hosik, Park, You-In, Lee, Jung-Hyun
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 15.08.2019
• Subjects: Forward osmosis; Interfacial polymerization; Polydopamine; Polyethylene; Thin film composite membrane; Polydopamine; Interfacial polymerization; Polyethylene; Thin film composite membrane; Forward osmosis
• ISSN: 0376-7388; 1873-3123
• DOI: 10.1016/j.memsci.2019.04.074

A thin film composite (TFC) forward osmosis (FO) membrane with high performance and superb durability was fabricated on a polydopamine (PDA)-modified polyethylene (DPE) support via an unconventional aromatic solvent-based interfacial polymerization (IP) method. The PDA coating uniformly hydrophilized the hydrophobic pristine polyethylene (PE) support, which enabled the long-term operation stability. The thin (∼8 μm) and highly porous support structure with interconnected pores was preserved after the PDA modification, leading to a remarkably low structural parameter (∼168 μm) of the support. In addition, the use of the toluene-based IP process allowed for the formation of a highly permselective polyamide selective layer on the hydrophilic DPE support, which was challenging with the conventional aliphatic solvent-based IP process. Hence, the prepared DPE-supported TFC (DPE-TFC) membrane exhibited unprecedented high FO performance, i.e., ∼4.5 times higher FO water flux and ∼63% lower specific salt flux (in FO mode) compared to the commercial HTI-CTA membrane. Furthermore, the DPE-TFC membrane possessed superior mechanical robustness, which guarantee durable operability and potential application even in mechanically harsh environments. Hence, the PE-supported FO membrane presents a new paradigm in FO membrane technology. [Display omitted] •FO membranes were fabricated using polydopamine-modified PE (DPE) supports.•DPE supports were uniformly hydrophilic while preserving their original structures.•The thinness, high porosity and enhanced hydrophilicity of DPE supports reduced ICP.•Toluene-based interfacial polymerization produced a highly permselective layer.•The prepared DPE-TFC membranes showed excellent FO performance and high durability.