SYNTHESIS AND CHARACTERZATION OF METAL-ORGANIC FRAMEWORK FOR THE REMOVAL OF CONGO RED DYE FROM WATER

This article discusses the synthesis and structural characteristics of metal-organic frameworks (MOFs), specifically ZIF-8 and ZIF-67, and their potential applications in the removal of toxic organic pollutants from water. These materials belong to the class of porous coordination polymers, which have attracted attention due to their unique crystalline structure, high specific surface area, and potential for tunable porosity and functional groups. Special emphasis is placed on studying the adsorption properties of ZIF-8 and ZIF-67 using the removal of the toxic anionic dye Congo red from aqueous solutions as an example, allowing an evaluation of their effectiveness as adsorbents. Research has shown that both materials exhibit high adsorption capacities, amounting to 74.15 mg/g for ZIF-8 and 81.27 mg/g for ZIF-67, attributed to the ability of dye molecules to penetrate the porous structure of the frameworks. The adsorption of Congo red corresponds to the Langmuir isotherm model, indicating predominantly monolayer interactions with the adsorbent surface. Kinetic analysis showed that ZIF-67 achieves 53.8% dye removal efficiency in 24 hours, while ZIF-8 achieves 46.6%, confirming the significant potential of these materials in chemical and environmental engineering for effective wastewater treatment.

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