Defect-rich covalently-crosslinked UiO-66(Zr)-NH2/PVC adsorption ultrafiltration membrane for effective phosphate ions removal from water

Abstract

BackgroundPhosphorus in wastewater is a major environmental concern. Very small phosphorus inputs in the environment can cause algal blooms that can deplete the dissolved oxygen and decrease the water quality, leading to eutrophication. Furthermore, some algal blooms produce toxins and bacterial growth that can cause human illness through exposure to contaminated water. Therefore, It is necessary to remove phosphorus before it is discharged to the environment. Methodsadsorbent enhanced adsorptive ultrafiltration (UF) has recently emerged as an advanced ion recovery technology with membrane filtration function and adsorption function, and is very effective in removing cationic bisphosphate and anionic phosphate. Significant findingsHerein, a novel defect-rich and covalently-crosslinked octanoic acid (OA)-UiO-66(Zr)-NH2/PVC adsorption ultrafiltration membrane are designed for removal of phosphate ions in water. The OA-UiO-66-NH2/PVC-33 membrane achieved the adsorption capacity (∼30 mgg−1) and higher removal efficiency (∼90%). The OA-UiO-66(Zr)-NH2/PVC ultrafiltration membrane exhibited a higher water flux of 266.9 L/(m2·h·bar) compared to those of pristine PVC and UiO-66-NH2/PVC. Filtration and cyclic stability experiments reveal that OA-UiO-66(Zr)-NH2/PVC membrane can maintain a high retention capacity and exhibit excellent regeneration performance after 5 cycles.