High performance ultrafiltration membrane based on modified chitosan coating and electrospun nanofibrous PVDF scaffolds

Liquids filtration technology as one of the paths to sustainable water use is getting more and more attention. A new type of high flux ultrafiltration (UF) or nanofiltration medium based on electrospun fibrous scaffold and ultrathin top barrier layer was fabricated recently. Based on this new method, the chitosan (CTS) which is one of the best top layer materials due to its hydrophilicity and high water-permeability was coupled with electrospun polyvinylidene fluoride (PVDF) nanofibers to compose a new type UF membrane. In this work, the chitosan was crosslinked and modified by glutaraldehyde (GA) and terephthaloyl chloride (TPC) to adjust its water resistance and surface properties. The modified membrane was characterized by FTIR, SEM, UV-spectra, static water contact angle analysis and filtration test. The modified membrane gets broader operating environment range and keeps a good flux rate and rejection efficiency in bovine serum albumin (BSA) filtration tests at 0.2 MPa, about 70.5 L/m(2) h, rejection efficiency >98% which are higher than that of 57.1 L/m(2) h, rejection efficiency similar to 98% of the commercial UF membranes, while the fouling of the membrane was kept at a very low level. This work may provide a practical possibility to the water filtration industry. (C) 2012 Elsevier B.V. All rights reserved.