In this work,a thin zirconium-based UiO-66 membrane was successfully prepared on an alumina hollow fiber tube by flow synthesis,and was used in an attempt to remove p-nitrophenol from water through a nanofiltration process.Two main factors,including flow rate and synthesis time,were investigated to optimize the conditions for membrane growth.Under optimal synthesis conditions,a thin UiO-66 membrane of approximately 2 um in thickness was fabricated at a flow rate of4 mL.h for 30 h.The p-nitrophenol rejection rate for the as-prepared UiO-66 membrane applied in the removal of p-nitrophenol from water was only 78.1%due to the existence of membrane defects caused by coordinative defects during membrane formation.Post-synthetic modification of the UiO-66 membrane was carried out using organic linkers with the same flow approach to further improve the nanofiltration performance.The result showed that the p-nitrophenol rejection for the post-modified membrane was greatly improved and reached over 95%.Moreover,the post-modified UiO-66 membrane exhibited remarkable long-term operational stability,which is vital for practical application.
