Adsorption Removal of Humic Acid from Water Using a Modified Algerian Bentonite

Abstract

In this study, the main objective is the preparation and the characterization of a modified Algerian bentonite based adsorbent by intercalation with hexadecyltrimethylammonium bromide (HDTMA). Natural and modified bentonites were characterized using thermogravimetric analysis (TGA), X-ray diffraction (XRD) and infrared spectroscopy (FTIR). The X-ray results indicate that the geometry of the interlayer space was changed by the intercalation of HDTMA cations and the basal spacing was increased from 1.34 to 1.96 nm. The adsorption efficiency of natural and HDTMA-bentonite was examined for humic acid (HA) removal by batch adsorption experiments under different operating conditions. The maximum monolayer adsorption capacity qm of HA was found to be 54.80 mg/g and 330.34 mg/g for HDTMA-bentonite and natural bentonite respectively. The kinetic study indicated that HA adsorption followed the pseudo-first-order model. Both natural and HDTMA-bentonite showed quite good capabilities in removing HA from aqueous solutions.