Mechanistic Issues Relating to Amine Functionalized Nanocellulose‐Metal Organic Framework PES/PLA Membranes for Methyl Orange Dye Removal: Coupling Adsorption and Persulfate Activation

This current study reports on the fabrication of a multifunctional polymeric amine functionalized nanocellulose metal–organic framework PES‐based membrane. The fabricated membrane coupled adsorption and oxidative degradation through persulfate activation for the removal of methyl orange dye. A modified phase inversion technique was used to synthesize the membranes, and the nanocomposite composition in the membranes was varied between 0.5% and 2.0%. The novel membrane showed good adsorption, removing ~70% of the dye and 98% in the combined adsorption‐degradation system within 60 min. The functionalized membranes showed improved performance characteristics when compared to the pristine membranes. The contact angle reduced from 76° to 54°, making the membranes more hydrophilic, while pure water flux increased from 204.21 to 291.83 Lm −2 h −1 bar −1 . The improved contact angle and flux show that the synthesized membranes have good fouling resistance, as evidenced by the membranes flux recovery ratio, which increased from 36% in pristine membranes to 95% in membranes with 2% CNF@ZIF‐8‐NH 2 composition. The effect of pH on the removal of MO dye was also evaluated, and the optimum pH was found to be 3, while the membranes pzc was found to be 5.5. Quenching tests revealed that during the degradation process, •SO 4 radicals were the dominant species responsible for the degradation of the dye molecules, and the mechanism of degradation followed both homogeneous and heterogeneous pathways. Analysis of the membrane stability showed that the membranes were stable, with dye removal efficiency reducing by 16% after 5 degradation cycles.