A kinetic and thermodynamic study of methylene blue removal from aqueous solution by modified montmorillonite

In this study, sulfonic acid-functionalized ordered nanoporous Na+-Montmorillonite (SANM) hasbeen utilized as the adsorbent for the removal of a cationic dye, methylene blue (MB), from aqueous solution by the batch adsorption technique. The optimum sorption conditions were found asfollowing: contact time 10 min, initial dye concentration 800 mg/L,adsorbent dose 0.3 g and temperature 25°C.The results indicate that the process is pH independent. Different thermodynamic parameters i.e., changes in standard free energy, enthalpy and entropy have also been evaluated and it has been found that the reaction was spontaneous and endothermic in nature. Inother hand Kinetic parameters havebeen investigated withpseudo first and second orderhave also beeninvestigated. The result experimental data indicate that pseudosecondorder equationfit better than the other.

کلیدواژه ها:

Na+-Montmorillonite ، Methylene blue ، Removal ، kinetic ، thermodynamic