Efficient removal of hazardous dyes/heavy-metal ions by in-house fabricated poly (vinylidene fluoride) thin-film nanocomposite membranes with functionalized Zr-based metal-organic framework

Abstract

The need for effective solutions to address removal of dyes and heavy metal ions from water has driven significant interest in membrane science and separation technology. This work explores the potential of EDTA-modified MOF-808 as a novel additive to enhance the performance of PVDF supported TFC membranes. The innovation lies in aiming the unique properties of MOF and the chelating properties of EDTA in rejecting the target pollutants. The thin film nanocomposite membranes fabricated in this study with optimized MOF-EDTA loading demonstrated remarkable improvement in hydrophilicity, surface smoothness, porosity, and morphology as confirmed by water contact angle, atomic force microcopy, water uptake, and scanning electron microscopy. The optimized membrane with 0.1wt% MOF-808-EDTA exhibited a water flux of 37.36 Lm-2h-1, a 2.7-fold increment compared to the unmodified one. This was complemented by 98.6%, 91.48%, 88.7%, and 88.96% rejections in hazardous heavy metal ions namely lead, arsenite, cadmium and mercury respectively along with more than 95% rejections for 50ppm of sunset yellow and reactive black 5 dyes. The study also highlights the significant enhancement in antifouling properties with a reduction in irreversible fouling from 41.5% to 5.68% along with a flux rejection ratio of 94.3%. These findings underscore the potential of EDTA-modified MOF as an additive in enhancing the performance and durability of TFC membranes paving the way for efficient and sustainable water treatment. The current study explores an innovative approach for mitigating heavy metal ion and dye pollution in water via fabrication of. © 2025 Published by Elsevier Ltd.