Adsorption of methylene blue on Cu(II)-exchanged montmorillonite.

Cu(2+)-exchanged montmorillonite (CEM) was prepared using the method of ion exchange reaction. The goal was to determine the adsorption of methylene blue (MB) onto montmorillonite and CEM. The results showed that treatment with Cu(2+) slightly reduced the adsorption of montmorillonite. Temperature, pH value, and ionic strength in the medium had greater or smaller effects on interaction between MB and the clay. The data obtained from MB adsorption onto the tested adsorbents followed the Langmuir and BET equations. Also, the adsorption processes were endothermic and spontaneous in nature.