Kinetics Study of Methylene Blue Adsorption Onto Activated Carbon by Means of Spectrophotometry

Abstract

Goal of this work is to explore adsorption phenomenon of methylene blue on activated carbon. The adsorption process was monitored at 30 0C and 50 0C. We used spectrophotometric method for concentration estimation and on the basis of obtained results we proposed kinetics mechanism and equilibrium isotherms. Adsorption has been found to be an efficient and economically cheap process to remove pollutants such as colors, dyes and metal impurities. Adsorption processes using activated carbons are widely used to remove pollutants from wastewater. By fitting experimental results, pseudo-second order and Elovichev model gave very satisfactory results with the correlation coefficient R = 0.99994 and R = 0.99973, successively. Equilibrium isotherms of the methylene blue on the activated carbon were determined and correlated with common isotherm equation Freundlich, Langmuir and Temkin model. Rate of adsorption increased with increase in experimental temperature, which goes in favor of endothermic process. Adsorption of methylene blue onto activation carbon is happening probably through chemisorption path.