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The present study reports the preparation of an activated carbon produced from buriti shells (AC b ) using ZnCl 2 as activating agent and its ability to remove methylene blue dye (MB) from aqueous solutions. The obtained AC b was characterized by N 2 adsorption–desorption isotherms, SEM and FT-IR. The results show that AC b presents microporous features with BET surface area ( S BET ) of 843 m 2 g −1 and functional groups common in carbonaceous materials. Adsorption studies were carried out and experimental data were fitted to three isotherm models (Langmuir, Freundlich, and Redlich–Peterson) and four kinetic models (pseudo-first order, pseudo-second order, Elovich, and intraparticle diffusion). The isotherm model which best fitted to experimental data was Redlich–Peterson. However, the g parameter of this model indicated that the adsorption of MB onto AC b occurs according to the mechanism proposed by Langmuir, which showed maximum monolayer adsorption capacity of 274.62 mg g −1 . Kinetic studies demonstrated that the Elovich model is suitable to describe the experimental data. Moreover, it was found that the intraparticle diffusion is the limiting step of adsorption process. |
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