Abstract
The applications of β-cyclodextrin (β-CD) in chlorine-resistant membranes have always faced the challenge of agglomeration at high concentrations. In this study, polyvinyl alcohol (PVA) modified β-CD was used as a monomer to prepare forward osmosis (FO) membranes with high chlorine resistance. Scanning electron microscope (SEM), Fourier transform infrared spectroscopy (FTIR), automated contact angle meter (CAM), electrodynamic analyzer (EA), X-ray photoelectron spectroscopy (XPS), and true color confocal microscopy (CSM) have been used to characterize the physicochemical properties of the FO membrane. The agglomerated β-CD affected the formation of the selective layer, resulting in reduced water fluxes ranging from 12.4 L m−2 h−1 to 1.75 L m−2 h−1. The modified TFC-PVA-β-CD FO membrane had a complete, defect-free selective layer, and water flux of 16.75 L m−2 h−1 at 1 M NaCl as a draw solution. FTIR spectra showed that the absorption peak intensity of the carbonyl (CO) group generated from β-CD and 1,3,5-Benzene tricarbonyl trichloride (TMC) increased after PVA modification. After 6 hours of chlorination, the reverse salt flux of the thin film composite (TFC) FO membranes abided by the following order: TFC (80.35 g m−2 h−1) > TFC-β-CD (60.95 g m−2 h−1) > TFC-PVA-β-CD (12.45 g m−2 h−1). The results indicated that the PVA effectively promotes uniform dispersion of β-CD. More chlorine-resistant ester bonds (-COO-) were formed in the TFC-PVA-β-CD FO membrane, so it possessed good chlorine resistance. This study provides a green, simple, and environmentally economical method for the preparation of chlorine-resistant FO membranes.
Published Version
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call