Magnetic Composite Nanofibers as Advanced Adsorbents for Toluidine Blue and Congo Red Dyes

• DOI: 10.1007/s10904-025-03591-0
• Publication Date: 2025-01-09T14:37:13Z
• Authors: Hajer Tlili; Anis Elaoud; Nedra Asses; Jesús A. Fuentes-...; Karima Horchani-N...; Mounir Ferhi
• Keywords: Congo red; Toluidine

This study introduces an innovative method to remove dyes using a composite material of magnetite nanoparticles (MNPs) immobilized in nanofibers (MNFs). Produced via a simple electrospinning method, the MNFs exhibited excellent adsorptive properties, including a uniform average diameter of 0.3 ± 0.06 μm, a BET surface area of 9.9457 ± 0.0363 m2 g−1, a pore volume of 0.02 cm3 g−1, and a pore size of 8.778 nm. Chemical and thermal analyses confirmed the composite’s characteristics. The adsorption performance of MNFs was assessed using two ionic dyes: cationic Toluidine Blue (TB) and anionic Congo Red (CR). Compared to MNPs, MNFs achieved significantly higher adsorption capacities, with values of 325 mg g−1 for TB and 350 mg g−1 for CR at a dye concentration of 1 g L−1. The adsorption kinetics were analyzed, fitting well with the Pseudo-Second-Order model. The MNFs demonstrated enhanced adsorption capacities, increasing by up to 15% for TB and 20% for CR compared to MNPs under identical conditions. These results underscore MNFs’ potential as effective adsorbents for dye removal, offering an environmentally friendly and cost-effective treatment for industrial wastewater.