Study of the elimination of methyl orange from aqueous solutions by natural and commercial adsorbents

The present study is concerned by the exploration of the capability of natural and synthetic adsorbents to retain methyl orange dye. The effect of key operating parameters such as contact time, adsorbent dosage, initial pH and initial dye concentration on retention capacity, were investigated for these adsorbents. Various isotherm models like Langmuir and Freundlich were tested for the adsorption isotherms determinations. The adsorption kinetics was studied testing first and second-order kinetic models. The rate of dye removal follows pseudo-second-order kinetic model, with correlation coefficients close to unity when experimental data were fitted in the model. The obtained results showed that Silica gel and peanut shells had a good adsorption capacity of methyl orange.