Abstract
L-cysteine (Cys) was adsorbed by bentonite (Ben) from aqueous solutions of variable concentrations and pHs. The raw materials and the adsorbed molecules (Ben-Cys) were characterized using X-ray diffraction (XRD), infrared spectroscopy (IR), thermal analysis methods (TG, DTG and DSC). The results indicated that the adsorption process depended strongly on pH, temperature and concentration of amino acid. Cysteine is specifically adsorbed on bentonite surface sites, probably through its