O estudo da montmorilonita como adsorvente de corantes em meio aquoso

Abstract

Studied the adsorption of the following dye: Orange Indosol, Rhodamine B, Congo Red and Blue Indosol about montmorillonite clay in an aqueous medium at temperatures of 288, 298, 308 and 318K. The best yields were obtained at temperatures of 288 and 298K. The process of removing these dyes was studied from kinetic and equilibrium data for each temperature. The Freundlich model was best represented the experimental data of adsorption isotherms for dyes at all temperatures considered. The kinetic model of pseudo-second order was the best fit to the experimental data of the interactions involved in the process. It was found that treating an endothermic process and the interactions dye / MTT increase the degree of spontaneity of reactions with increasing process temperature. For the XRD patterns obtained for samples of LI / MTT, VC / MTT and AI / MTT was possible to verify that all incident angles show no major changes in essentially overlap mainly in the incidence angle (2θ) when compared to MTT. Thermogravimetric analysis shows that the thermal decomposition of the complete MTT began about 30 ° C and was completely up to 1000 ° C and four different weight losses are identified. The intensity of the absorption bands present in the spectrum in the infrared region was reduced after adsorption of the dyes also showing that the adsorption of the dye does not alter the structure of montmorillonite.