Ultrathin Support-Free Membrane with High Water Flux for Forward Osmosis Desalination
In this work, an ultrathin polyamide (PA) membrane was fabricated via in situ removing polysulfone (PSF) substrate from the PSF-PA forward osmosis membrane for the first time. The physicochemical properties of the PA membranes were confirmed by means of surface morphology, chemistry analysis, and surface charge characterization. The performance of PA, PSF-PA, and physically combined PSF+PA membrane was compared in terms of water flux, reverse salt flux, and selectivity. The flux performance of these three membranes followed the order of PA>PSF-PA>PSF+PA membranes, and the possible mechanism for their performance was proposed. Compared with home-made PSF-PA and PSF+PA membranes, the ultrathin PA membrane had high water flux (i.e., 80.54 LMH) due to its low membrane resistance and minimized internal concentration polarization under same operation conditions (i.e., DI water feed solution, 1.0 M NaCl draw solution, and AL-FS orientation). This study would provide insights on the preparation and application of ultrathin PA membranes with high permeability in the context of global water/energy-related crisis.
KeywordsIn situ fabrication Ultrathin membrane Polyamide Water flux Forward osmosis
This work was financially supported by the Suihua Science and Technology Project (No. SHKJ2016-033), the Doctor Research Foundation of Suihua University (No. SD13002) and the Scientific and Technological Research Projects of Suihua University (No.K201701001).
Compliance with Ethical Standards
Conflict of Interest
The authors declare that they have no conflict of interest.
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