Highly permeable thin film nanocomposite membrane utilizing a MoS2@NH2-UiO-66 interlayer for forward osmosis removal of Co2+, Sr2+ and Cs+ nuclide ions

Abstract

Novel MoS2@NH2-UiO-66 thin-film nanocomposites with interlayer (TFNi) membranes were developed to improve forward osmosis (FO) membrane performance. The prepared TFNi membrane shows a high water permeability of 38.13 ± 0.8 L m−2h−1 and low reverse salt flux (JS/JV) of 0.038 when using 2.0 mol/L sodium chloride as the draw solution (DS) and deionized water as the feed solution (FS) under AL-FS mode. This is attributed to MoS2@NH2-UiO-66 modifications of substrate properties, which fix m-phenylenediamine (MPD) on the nanomaterial surface, increase the polyamide (PA) layer crosslinking degree on the material surface, and allow trimesoyl chloride (TMC) to stay on the substrate surface during interfacial polymerization (IP) and prevent accumulation in the pores of the substrate. Therefore, the trade-off between permeability and selectivity of TFN membranes is overcome. The MoS2@NH2-UiO-66 TFNi membrane effectively removes Co2+, Sr2+ and Cs+ from aqueous solution via FO retention. When Co2+, Sr2+ and Cs+, nuclide ions with small hydration radii, are present in the FS at 20 mg/L, the retention rates are maintained at 99.6%, 99.7% and 97%, respectively, which are higher than those of existing commercial membranes. These results indicate the potential of MoS2@NH2-UiO-66-TFNi membranes for treatment of nuclide ions in wastewater.