Bio-sorption of Methylene Blue by Defatted Seed of Adansonia digitata

Abstract

The study was carried to evaluate the ability of defatted seed of Adansonia digitata (DFSE) to remove methylene blue dye from contaminated water. The optimum parameters such as contact time, particle size, absorbent dose, initial dye concentration, and pH were investigated by performing batch experiments models. The kinetics and the isotherms adsorption were evaluated by varying the initial concentration and using the optimum parameters. The optimum of contact time is 90 min and the removal capacity is 99.34 %. A mass of 700 mg is sufficient to reach the maximum removal of methylene blue (99.44 %). The maximum adsorption is obtained with an initial methylene blue concentration of 75 ppm (98.53 %). The optimum particle size is 100 mm. The kinetics of the adsorption process are in accordance with the pseudo-second order model. Experimental values of the adsorption capacity are close proximity to the optimum values predicted by the pseudo-second order model. The Langmuir, Freundlich, Dubinin-Radushkevich and Tempkin isotherms are not suitable to explain the experimental isotherm.