Fabrication of TiO2@ZIF-67 metal organic framework composite incorporated PVDF membranes for the removal of hazardous reactive black 5 and Congo red dyes from contaminated water.

[Display omitted] • TiO 2 @ZIF-67 metal organic framework contained PVDF ultrafiltration flat sheet membranes were fabricated. • Membranes were characterized by various techniques. • The reactive black 5 dye was rejected in 97.4%, 92.2%, and 84.84% in acidic, basic and neutral conditions respectively by TZM-2 membrane. • Similarly, the Congo Red dye was rejected in 89.4%, 95.68%, and 92.4% in acidic, neutral and basic conditions respectively by TZM-2 membranes. Novel application of TiO 2 @ZIF-67 composite incorporated poly (vinylidene fluoride) (PVDF) mixed matrix flat-sheet membranes for treating the water contaminated with hazardous reactive black 5 and congored dyes was the crux of this work. The composite was characterized by FTIR, BET, XRD, zeta potential and particle size, and TGA. The as-synthesized composite was embedded in the PVDF polymeric matrix and flat-sheet-membranes were fabricated adopting the NIPS method followed by the different characterizations like scanning electron microscopy, EDS, elemental mapping, contact angle, atomic force microscopy, surface energy, and XPS. Results of the performance studies showed an enhanced pure water permeability from 150.99 Lm-2h−1 for neat membrane to 261.39 Lm-2h−1 for TZM-2. The reactive black 5 dye was rejected in 97.4 %, 92.2 %, and 84.84 % in acidic, basic and neutral conditions respectively by TZM-2 membrane. Whereas, the PVDF membranes without the composite showed rejections of 83.19 %, 82.5 %, and 72.1 % respectively in acidic, basic, and neutral conditions. The Congo Red dye was rejected in 89.4 %, 95.68 %, and 92.4 % in acidic, neutral and basic conditions respectively by TZM-2 membranes. Whereas, the PVDF membranes without the composite showed rejections of 82.8 %, 91.9 %, and 85.4 % respectively in acidic, neutral and basic conditions. [ABSTRACT FROM AUTHOR]