Adsorption of Humic Acid from Aqueous Solution on Different Modified Bentonites
Résumé
The main objective of this work is the preparation and the characterization of a modified bentonites based adsorbents by intercalation with DMSO and DMF. Modified bentonites were analyzed using thermal analysis (TGA), infra-red analysis (FTIR) and X-ray diffraction. The X-ray results indicate that the geometry of the interlayer space was modified for all bentonites, and the interlayer distances observed are in the order of 1 to 1.41 nm. The adsorption ability and efficiency of different bentonites was tested for the removal of humic acid HA in aqueous solutions. In fact, batch adsorption experiments were carried out under different conditions including the adsorbent dose, the contact time, the initial humic acid concentration, the solution pH, in order to investigate their effects on the retention capacity of the modified bentonites. The maximum adsorption capacity of HA was found to be 16.97 mg/g, 14.65 mg/g, and 11.2 mg/g for DMF-bentonite, DMSO-bentonite and bentonite respectively. In conclusion Modified bentonites showed quite good capabilities in removing HA from aqueous solutions