Argila de ocorrência de Alto Diamantino–MT utilizada para adsorção de cádmio : estudos cinéticos e termodinâmicos

Abstract

Esmectite clay mineral has been collected from Alto Diamantino – MT, Brazil. The natural clay sample was characterized by elemental analysis, X-ray diffraction, scanning electron microscopy, thermal analyses, infrared spectroscopy (FTIR) and nuclear magnetic nuclei of 29Si and 13C. The esmectite natural sample was functionalized with the silane N-(3- Trimethoxysilyl)-Propyl- Ethylenediamine. The ability of this material to remove divalent metal Cd2+ from aqueous solution was followed by a series of adsorption isotherms at room temperature and pH 4.0. The maximum number of moles adsorbed was determined to be 1,44.10-6 mmol. g- ¹. The kinetic data were better fitted to Sips pseudosecond order model. Thermodynamics indicated the existence of favorable conditions for Cd2+ interactions with the clay surface of natural and modified samples.