Removal of methylene blue by using porous carbon adsorbent prepared from carbonized chestnut shell

Carbonized chestnut shell was investigated as a low cost adsorbent for the adsorption of methylene blue (MB) from aqueous solution. Some parameters like the effects of initial dye concentration, initial pH value of solution and contact time of phases were investigated. The equilibrium was attained in 120 minutes. The isotherm models of Langmuir, Freundlich and Dubinin Raduskhevich (DR) were applied to the experimental data and Langmuir and DR adsorption models fit better than the Freundlich model. The maximum MB mono adsorption capacity was found to be 5.13 mg x g(-1) obtained by Langmuir model. This value of carbonized chestnut shell was comparable to the adsorption capacities of some other adsorbent materials for dyes. The pseudo first order, second order and intra particle diffusion models were chosen for analyzing adsorption rate data. The adsorption reaction progressed according to the pseudo second order kinetic and Weber Morris diffusion was also effective in the adsorption phenomena. The thermodynamic parameters were also calculated.