Synthesis of highly stable UiO-66-NH2 membranes with high ions rejection for seawater desalination

Abstract Compact and phase-pure UiO-66-NH2 membranes were synthesized on the 3-aminopropy-ltriethoxysilane (APTES) modified macroporous Al2O3 tubes through a repeated synthesis strategy. APTES acts as a molecular linker for anchoring the metal ions onto the support surface to promote the nucleation and the crystallization of UiO-66-NH2 membrane. Therefore, well-intergrown UiO-66-NH2 membranes could be prepared through a repeated synthesis method on the APTES-modified macroporous Al2O3 tubes. The developed UiO-66-NH2 membranes were evaluated for seawater desalination by pervaporation. It is found that the UiO-66-NH2 membranes show high desalination performances attributing to the narrow pore size which is exactly in between the size of water molecules and hydrated ions. With increasing the feed temperature from 318 to 363 K, the water fluxes increase from 1.5 to 12.1 kg m−2 h−1, with ions rejections of above 99.7%. Further, the UiO-66-NH2 membranes display high stability for a long time in seawater desalination, which is very promising for seawater desalination.