Porous metal organic framework CuBDC nanosheet incorporated thin-film nanocomposite membrane for high-performance forward osmosis

A thin-film nanocomposite (TFN) membrane containing compatible 2D metal-organic framework (MOF) nano-filler in the active layer was developed to improve water permeability and antifouling capacity without compromising the selectivity for forward osmosis (FO) applications. The MOF nanosheet (copper 1,4-benzenedi-carboxylate nanosheets, CuBDC-NS) was successfully incorporated into polyamide (PA) active layer during the interfacial polymerization, as revealed by transmission electron microscope, X-ray diffraction and X-ray photoelectron spectroscopy. The TFN membrane exhibited higher water permeability and lower reverse solute flux (J(s)) compared to the pristine membrane. About 50% increase in FO water flux (J(w)) and 50% decrease in specific reverse solute flux (J(s)/J(w)) were observed for the TFN membrane with 0.12 wt/v % CuBDC-NS compared to the control, when 1.0 M NaCl was used as draw solution in the active-layer facing feed-solution (AL-FS) mode. In the continuous flow test using real wastewater as the feed-solution, the TFN membrane demonstrated a higher water flux and a slower water flux decline than the pristine one. The antifouling behavior of the CuBDC incorporated TFN membrane was associated with the increased hydrophilicity and biocidal ability. These results highlight the potential of CuBDC-NS incorporated TFN membranes to be used in FO processes for water desalination and wastewater treatment.