Study on adsorption behaviors of strong basic resin IRA-400 for fumaric ACID

The adsorption behavior of strong basic resin IRA-400 for fumaric acid was studied through static experiments. The results concluded that, comparing with IRA-94, this resin was less influenced by pH. The optimal pH value for adsorption in the medium of fumaric acid was pH 3.5 and the statically saturated adsorption capacity was 1.466mmol/g wet resin. The adsorption data were correlated with Freundlich isotherm equation, and the correlative coefficients (R²) all exceeded 0.99 at 298.15K, 308.15K and 318.15K. Characteristic parameter of this equation n>1. Thermodynamic parameters such as AG, AS, AH were calculated from the slope of the linear plot of InQ_e against InC_e. The negative value of AG, AS, and AH indicated that the adsorption process was exothermic, spontaneous and thermodynamically favourable, lower temperatures favored the process. The kinetics experiments showed that the liquid film diffusion was the rate-controlling step and furthermore the diffusion coefficient was calculated.