Green Synthesis of a Melamine-Based MOF and Its Performance in Wastewater Treatment

Cationic dyes like methylene blue (MB) and basic red 46 (BR-46) pose significant environmental risks due to their toxicity and persistence in aquatic systems. This study aims to enhance adsorption efficiency by modifying a melamine-based metal-organic framework (MOF). By altering the solvent during synthesis, a porous structure, [Cu(ɳ1-OAc)(µ-OC2H5)(MA)]2 (CMP-Et), was successfully derived from [Cu(ɳ1-OAc)(µ-OCH3)(MA)]2 (CMP-Me) using low-cost ethanol as a green solvent. The materials were characterized using XRD, FT-IR, and SEM. The removal efficiency of MB and BR-46 at an initial concentration of 20 mg/l was found to be 80 and 37%, respectively. The adsorption capacity of CMP-Et for the removal of MB and BR-46 was calculated to be 161 and 74 mg/g, respectively. The adsorption data for these dyes were consistent with the Langmuir and the Freundlich/Temkin isotherms, respectively, and followed pseudo-second-order kinetics. This work demonstrates the potential of cost-effective MOFs synthesized from inexpensive solvents like ethanol for efficient textile wastewater treatment.