Poly(methyl methacrylate-ethylene glycol dimethacrylate) copolymer for adsorptive removal of erythrosine dye from aqueous solution

摘要

The preparation and characterization of poly(methyl methacrylate-ethylene glycol dimethacrylate), (poly(MMA-EGDMA)) polymer for erythrosine adsorption has been investigated. Erythrosine is a synthetic red dye used to color food. Water-soluble acid dyes have caused serious water pollution. Poly(MMA-EGDMA) polymer showed better adsorption performance for erythrosine at acidic region and at 30 degrees C. The adsorption process had also been verified by Langmuir and Freundlich adsorption isotherms at 30, 40, and 50 degrees C. Free energy of adsorption ( increment G degrees), enthalpy ( increment H degrees), and entropy ( increment S degrees) changes were calculated to predict the nature of adsorption. The estimated value for increment G degrees was calculated as -125.6 kJ/mol at 303 K (30 degrees C). The estimated value for increment H degrees was found as -60.69 kJ/mol at 303 K. The negative value for increment H degrees indicated that the adsorption of erythrosine on poly(MMA-EGDMA) polymer was an exothermic process.