Adsorption of Direct Dyes from Aqueous Solutions by Gelatin Microspheres: Kinetics and Equilibrium
This study discussed the use of gelatin microspheres (GMSs) prepared by the inverse suspension cross-linking reaction for the removal of direct dye from aqueous solution. The Biot number was determined using internal mass transfer coefficient and the external mass transfer coefficient estimated using Mathews and Weber model. The Biot number estimated provides that internal mass transfer controls the mechanism of adsorption of direct dye onto GMSs. The Langmuir and Freundlich adsorption models were applied to describe the equilibrium isotherms. The Langmuir monolayer adsorption capacity of GMSs was estimated as 584.2 mg/g for direct red 81 (DR81) and 566.5 mg/g for direct blue 78 (DB78). The quite high adsorption capacity GMSs will provide an important advantage for use of this material in the treatment of direct wastewater.
Xiaoming Qian and Huawu Liu
B. Y. He et al., "Adsorption of Direct Dyes from Aqueous Solutions by Gelatin Microspheres: Kinetics and Equilibrium", Advanced Materials Research, Vols. 332-334, pp. 1577-1581, 2011