Absorption Equilibrium and Thermodynamics of Fenugreek Yellow Pigment on Macroporous Resins
The adsorption equilibrium and thermodynamics of pigment extracted from Fenugreek after degumming on macroporous resins was investigated under differentinitial concentrations. The suitability of the Freundlich and Langmuir adsorption models to the equilibrium data was investigated. The model fitness was determined by R2 . Thermodynamic parameters were calculated by the Van’t Hof equation.The results showed that Freundlich model gave a better fit of adsorption isotherms than Langmuir models. The positive value of enthalpy(∆H) indicated that the adsorption was endothermic, the negative value of Gibbs free energy (∆G) showed the spontaneous and favoured nature of adsorption, and the entropy(∆S) was positive.The resins LS-46 showed an effective adsorbtion for Fenugreek yellow pigment.
Zhong Cao, Lixian Sun, Xueqiang Cao, Yinghe He
F. Han et al., "Absorption Equilibrium and Thermodynamics of Fenugreek Yellow Pigment on Macroporous Resins", Advanced Materials Research, Vols. 233-235, pp. 91-94, 2011