Thermodynamics and kinetics of adsorption of molybdenum blue with D301 ion exchange resin

The adsorption behavior of D301 for molybdenum blue was investigated. The thermodynamics parameters in adsorption process were calculated and the adsorption kinetics was studied. The experimental results show that the adsorption characteristic of D301 for molybdenum blue fits well with the Freundlich adsorption isotherm equation. In the adsorption process of D301 for molybdenum blue, both the enthalpy change ΔH and entropy change ΔS are positive, while the free energy change ΔG is negative when temperatures are in the range of 303-333 K. It is indicated that the adsorption is a spontaneous and endothermic process, and the elevated temperatures benefit to the adsorption. Kinetic studies show that the kinetic data are well described by double driving-force model, and the adsorption rate of molybdenum blue on D301 is controlled by the intraparticle diffusion during the adsorption process. The total kinetic equation is determined.