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

Abstract

The synthesis of covalent triazine framework (CTFs) conventionally requires 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)tripoline nanocomposite was successfully synthesised and characterised by FT-IR, DSC, TGA, XRD, SEM and VSM analyses. The developed material demonstrates 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% 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 modelling indicate that the adsorption follows a pseudo-second-order mechanism, while isotherm analysis confirmed suitability of Langmuir adsorption model, suggesting mono layer adsorption. Reusability testing further showed that adsorption retained over 65% removal efficiency after ten successive cycles, establishing in potential as a sustainable, cost effective and recyclable material for waste water treatment and dye remediation applications.