Green‐Synthesized ZrO ₂ ‐Integrated Cellulose‐Nanofibers–Chitosan Composite Membrane for Sustainable Removal of Pharmaceut

ABSTRACT

Pharmaceutical residues in water pose a significant threat to both the environment and human health. This article discusses a dual‐functional cellulose nanofibers‐chitosan membrane that incorporates ZrO ₂ nanoparticles, allowing for simultaneous adsorption and photocatalytic degradation. ZrO ₂ nanoparticles were synthesized by using Lychee peel extract as a bio‐reducing reagent, an eco‐friendly, chemical‐free approach, as cellulose nanofibers and chitosan have an abundance of hydroxyl and amino groups, which favor adsorption. At the same time, ZrO ₂ exhibits photocatalytic activity under natural solar light. The nanoparticle and membrane were characterized by using techniques such as particle size analysis, FTIR, FE‐SEM, UV–Vis, and XRD, confirming that the membrane has a homogeneous structure and ZrO ₂ has a crystalline structure. Its performance was tested against Metronidazole (MNZ) and Nifedipine (NIF) in simulated wastewater, demonstrating removal efficiencies of 68% and 55% within 120 min, respectively. Degradation followed a first‐order kinetic model. The membrane retained over 90% efficiency after five reuse cycles and demonstrated excellent stability. The renewable biopolymer–nanoparticle composite showed rapid adsorption and in situ degradation under eco‐friendly conditions, without secondary pollution, making it highly suitable for pharmaceutical and decentralized wastewater treatment. Future research will focus on performance optimisation in real wastewater systems for large‐scale applications.