Synthesis, characterization and potential application of organobentonite in removing 2,4-DCP from industrial wastewater

Three bentonite modified with organic surfactants were used to remove 2,4-dichlorophenol (2,4-DCP) from aqueous solution. Of the three bentonites studied, DK3, modified with octadecyl dimethyl benzyl ammonium chloride (ODBAC), was found to be most effective and the conditions affecting batch adsorption of 2,4-DCP were evaluated. The adsorption data fit the Langmuir isotherm model well predicting a high adsorption capacity of 281.8 mg/g at 30 degrees C. A pseudo-second-order model was used to calculate the corresponding rate constant of 10.35 mg/g min(-1) at 30 degrees C. Thermodynamic parameters demonstrated that the overall adsorption process was exothermic and spontaneous. Furthermore. DK3 was characterized by scanning electronic microscopy (SEM), specific surface area (SSA), X-ray powder diffraction (XRD) and Fourier transform infrared (FTIR) spectrometer, which provided evidence of morphological properties and the adsorption of 2,4-DCP onto DK3. Finally. DK3 was used to remove >92% of 2,4-DCP from industrial wastewater having an initial concentration of 10.0 mg/L. (C) 2010 Elsevier B.V. All rights reserved.