REMOVAL OF METHYLENE BLUE DYE BY ACTIVATED EGYPTIAN BENTONITE CLAY

Abstract

The aim of this study was the activation of Egyptian calcium bentonite clay, which was obtained from the El Alamein area, northern Egypt, to use it in the removal of methylene blue dye. Egyptian bentonite was crushed, ground in a ball mill, purified using magnetic separation, treated by 0.1N acetic acid, and finally activated by acid activation (HCl, H2SO4) and alkali activation (Na2CO3, NaOH) using 1, 3, 5, 7, and 9 percent of acids and alkalis. The samples were characterized by XRF, cation exchange capacity (CEC) and free swelling. A 5 % Na2CO3 activated sample was chosen for methylene blue dye removal due to its best swelling and cation exchange capacity results. Adsorption studies were performed to evaluate the influence of various experimental parameters (pH, temperature, initial concentration, bentonite dose, and time effect). Methylene blue removal was optimum at 40 oC, pH 7, 40 min, 200 ppm MB and using 1 g/L activated bentonite as adsorbent dose.