Removal of cationic dye from aqueous solution by a food waste: Potato peel [Elimination d'un colorant cationique dans une solution aqueuse par un déchet alimentaire: Epluchure de pomme de terre]

In this study,the adsorption of methylene blue dye from aqueous solution,on low cost adsorbent,potato peel,was studied using batch experiments. the characterization of the adsorbent was performed by scanning electron microscope (sem) coupled with edx and fourier transforms infrared spectrometer (ftir). the effect of adsorbent dose,initial dye concentration,contact time,ph and temperature was investigated. the kinetic data were fitted to the pseudo-first order and pseudo-second order models,and it is revealed that the adsorption of methylene blue onto potato peel follows the pseudo-second order model for all investigated initial dye concentration. the isotherms of adsorption data were analyzed by langmuir and freundlich models. it was found that the adsorption process could by described be the langmuir isotherm (r2=0.995),the maximum adsorption capacity,obtained from the langmuir isotherm plot was 32.70 mg.g-1.the thermodynamic parameters such as enthalpy δh°,entropy δs° and free energy δg° have also been evaluated to predict the nature of adsorption. the results indicate that the adsorption process is an exothermic,spontaneous physisorption.