Hydrophobically functionalized MIL-101/PEBA/PVDF composite membranes for phenol recovery by pervaporation

The recovering of phenolic compounds from waste waters is of vital significance owing to their strong toxicity, carcinogenicity and potential biological accumulation. Herein, different organic ligands-functionalized MIL-101 particles were synthesized and introduced into the polyether block amide (PEBA) matrix to construct excellent mixed matrix membranes (MMMs) for the permselective pervaporation of phenol. A range of characterization techniques were employed to investigate the physicochemical properties of these MIL-101 based particles and the resultant membranes. It was found that the incorporation of ligand-modified MIL-101 demonstrated better interfacial compatibility and hydrophobicity than the unmodified MIL-101. The BMIL-101/PEBA-3 membrane exhibited optimum separation factor of 12.47 and corresponding total flux of 1711.71 g·m −2 ·h −1 at 50 °C for a 1000 ppm phenol solution. The separation factor increased by 4.83 % versus FMIL-101/PEBA-3 membrane. However, in comparison to the original PEBA polymer membrane, the total flux and separation factor climbed by 16.96 % and 10.95 %, respectively, whereas the MMMs introducing unfunctionalized MIL-101 (3 wt%) exhibited a reduction in the phenol separation factor. Effects of polymer solution concentration, casting solution thickness, filler content, operating temperature, and phenol concentration on membrane separation performance were explored systematically. What’s more, the BMIL-101/PEBA-3 membrane also presented outstanding long-term stability for 84 h, which also provides novel guidelines to develop high-performance membranes for phenol recovery.