Covalent triazine-capped Fe3O4 nanocomposites for efficient dye remediation: structural insights, adsorption mechanism, and recyclability

Abstract

The synthesis of covalent triazine frameworks (CTFs) conventionally requires a prolonged reaction time, particularly when prepared through nucleophilic substitution between 2,4,6-trichloro-1,3,5-triazine (TCT) and amino acid-based functional monomers. In this study, a Fe₃O₄-adn-(1,3,5-triazine-2,4,6-triyl)triproline nanocomposite was successfully synthesized and characterized using FT-IR spectroscopy, DSC, XRD, SEM and VSM analysis and TGA. The created substance demonstrated excellent adsorption proportion for the removal of hazardous industrial dyes, including Reactive Red 195 (RR-195), Reactive Blue 222 (RB-222), and Reactive Black 5 (RB-5). Batch adsorption studies at 10% (w/v) dye concentrations under alkaline conditions revealed high removal efficiencies of 95.8% (RR-195), 95.0% (RB-222), and 94.6% (RB-5) from real industrial effluents. Kinetic modeling indicates that the adsorption follows a pseudo-second-order mechanism, while isotherm analysis confirmed the suitability of the Langmuir adsorption model, suggesting monolayer adsorption. Reusability testing further showed that the adsorbent retained over 65% removal efficiency after ten successive cycles, establishing its potential as a sustainable, cost-effective and recyclable material for waste water treatment and dye remediation applications.