Adsorption of a cationic dye,Methylene Blue,onto Moroccan Illitic Clay

In this study,moroccan illitic clay (mic) of khemisset regionthat was characterised by x-ray diffraction has been used as a low cost adsorbent in the removal of a cationic dye,methylene blue(mb),from aqueous solution by a batch adsorption technique. the effects of various experimental parameters such as solution ph,initial dye concentration,contact time,temperature,adsorbent masses and stirring speed were investigated. the results showed that basic ph and high stirring speed were favourable for the adsorption of dye,and the adequate equilibrium time for the adsorption of methylene blue onto moroccan illitic clay was 60min.the experimental data were analysed by the linear form of langmuir,frendlich,temkin and dubinine-radushkevich isotherm models and showed a good fit with the langmuir isotherm model. adsorption kinetic and its mechanism were studied using pseudo first order kinetic equation,second order kinetic equation and intra-particle diffusion model. the adsorption kinetic followed the pseudo second order equation that involved two steps for the dye investigated in this work. thermodynamic parameters were also evaluated and revealed that the adsorption of methylene blue onto moroccan illitic clay was spontaneous,and exothermic in nature.