A novel crosslinking technique towards the fabrication of high-flux polybenzimidazole (PBI) membranes for organic solvent nanofiltration (OSN)

• Published in: Separation and purification technology Vol. 209; pp. 182 - 192
• Main Authors: Davood Abadi Farahani, Mohammad Hossein, Chung, Tai-Shung
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 31.01.2019
• Subjects: Crosslinking; Green solvent; Membrane; Organic solvent nanofiltration (OSN); Polybenzimidazole (PBI); Solvent resistant nanofiltration (SRNF); Polybenzimidazole (PBI); Crosslinking; Membrane; Solvent resistant nanofiltration (SRNF); Green solvent; Organic solvent nanofiltration (OSN)
• ISSN: 1383-5866; 1873-3794
• DOI: 10.1016/j.seppur.2018.07.026

[Display omitted] •A novel crosslinking method was proposed to design high-flux PBI membranes.•A solution containing TMC and 2-MeTHF was used to modify the PBI membranes.•The modified membranes are tested for organic solvent nanofiltration applications.•PBI membranes showed promising permeance for polar and nonpolar solvents.•TMC modified membranes exhibited outstanding rejections for various solutes. A green crosslinking method has been proposed to design high-flux polybenzimidazole (PBI) membranes for organic solvent nanofiltration (OSN). Integrally skinned asymmetric PBI membranes were crosslinked using a solution containing trimesoyl chloride (TMC) and environmentally benign 2-methyl tetrahydrofuran (2-MeTHF) for the first time. The separation performance of the crosslinked PBI (X-PBI) membranes towards various solutes and solvents, including polar and nonpolar solvents, have been carefully studied. The X-PBI membrane shows a rejection of 99.6% to remazol brilliant blue R (MW of 627 g/mol) while it has pure acetonitrile, acetone, ethanol, and isopropanol permeances of 40.7, 29.0, 13.8, and 5.8 LMH/bar at 10 bar, respectively. Moreover, the X-PBI membrane exhibits superlative performance during the 2-step filtration of tetracycline, an antibiotic compound with a MW of 444 g/mol. It has rejections of 90.4% and 97.8% in the first and second steps of filtration, respectively. The X-PBI membrane is also able to concentrate solutions containing L-α-lecithin, a food additive with a MW of 758 g/mol, from hexane. It has a L-α-lecithin rejection of 92% and a pure hexane permeance of 80.8 LMH/bar at 10 bar. Besides, it shows great potential to separate mixed dyes and stable OSN performance during 96-h continuous tests.