S-ZIF-8/PEBA/ZIF-8 pervaporation membrane with in situ growing of ZIF-8 active layer on the surface owing outstanding phenol enrichment performance

Background Phenol and its chemical derivatives, as an essential chemical material, are indispensable for the synthesis of many kinds of polymers. However, they are highly toxic, carcinogenic, and often found in aqueous effluents. Pervaporation (PV) has been widely used to recover organic compounds from wastewater, because it can allow the permeable components in aqueous solution to pass through the membrane preferentially without any regeneration operation and additives. Methods Herein, a gradient PV membrane (S-ZIF-8/PEBA/ZIF-8) was constructed by embedded ZIF-8 into PEBA matrix, and then ZIF-8 active layer was in situ grown on the surface of PEBA/ZIF-8 membrane for phenol enrichment. Significant findings the prepared S-ZIF-8/PEBA/ZIF-8 membrane exhibits outstanding performance of both adsorption selectivity and diffusion selectivity for phenol molecules, which is attributed to the imidazole ring skeleton of ZIF-8 can interact with phenol molecules to form π-π stacking. Moreover, S-ZIF-8/PEBA/ZIF-8 membrane presents excellent separation performance with separation factor and flux of 109.3 and 215.85 g/m2·h, respectively, with feed phenol concentration of 0.8 wt% at 70 oC. In addition, S-ZIF-8/PEBA/ZIF-8 membrane also demonstrates excellent long-term stability means to enrich phenol, which has great prospect for practical application in phenol recover from waste water.