Study and modeling of the kinetics methylene blue adsorption on the clay adsorbents (Pyrophillite,Calcite) [Etude et Modélisation de la Cinétique d'Adsorption du Bleu de Méthylène sur les Adsorbants Argileux (Pyrophillite,Calcite)]

This article studies adsorption in system batch of a methylene blue cation dye,(largely used in several sectors) on two moroccan clays,pyrophillite of the area of akka,and calcite of the area of taounate. for that,we carried out a parametric study of adsorption,by studying the effect of several important parameters on the capacity fading of material used,in particular,the time of contact (equilibrium is established at the end of 15 minutes),the concentration of adsorbent,the ph,the agitation velocity,and the temperature. the experiments have demonstrated the determining role of these parameters. a kinetic study was carried out and kinetic models were applied to experimental results such as pseudo-first order,pseudo- second order. isotherms of adsorption were carried out for the dye of methylene blue,their modeling was carried out by applying models known such as langmuir,freundlich. the maximum capacity of adsorption of clay pyrophillite is of 19,608 mg.g-1,and that of clay calcite is of 18,776 mg.g-1,for a concentration of methylene blue of 20 mg/l,a ph=6,at a temperature 20°c,and an amount of the adsorbent of 1g/l. on the other hand,various techniques for characterizing the adsorbent were used. in addition,tests regeneration of the adsorbent was conducted in the laboratory by desorption of cations methylene blue dye adsorbed to examine the possibility of reuse of the adsorbent several times.