Synthesis of melamine-isocyanurate-based hyper-cross-linked resin for ultrahigh removal of chlorophenols from aqueous solutions

Chlorophenols, common organic pollutants, released from the various industrial processes are toxic and persistent in nature, bearing acute and chronic effects on human health. Herein, we report the synthesis of a novel triazine-based resin for the adsorptive removal of chlorophenols (CPs), namely chlorophenol (CP), dichlorophenol (DCP), and trichlorophenol (TCP). The resin, dubbed as MAICY, was synthesized in a straightforward fashion in a single step from the condensation of commercially available melamine and tris(2,3-epoxypropyl) isocyanurate. MAICY was characterized by diverse techniques including FESEM, FT-IR, solid (CP-MAS) ¹³C-NMR, and TGA. Various adsorption parameters such as the effect of pH of the solution, adsorbent dosage, CPs concentration, and adsorption temperature were thoroughly studied and optimized. Compared to other CPs, the adsorption capacity (q_e) of TCP (76 mg g⁻¹) at pH = 7 was found to be the highest, attaining a rapid adsorption equilibrium within 10 min. The kinetics data for adsorption of CPs were well fitted by pseudo-second-order rate equation with the value of R² = 0.9863–0.9983, close to 1.000. Within the applied adsorption isotherms, the Freundlich model was observed to be the best fit for the adsorption of CPs (R² = 0.9734–0.9947). Moreover, MAICY exhibited very good reusability and recyclability in synthetic wastewater (SWW) samples up to five consecutive cycles of adsorption–desorption for CP, DCP, and TCP removal. Graphical abstract: [Figure not available: see fulltext.].