Adsorption characteristics, isotherm, kinetics, and diffusion of modified natural bentonite for removing the 2,4,5-trichlorophenol

作者：Zaghouane Boudiaf H^*; Boutahala Mokhtar; Sahnoun Sousna; Tiar Chafia; Gomri Fatima

来源：Applied Clay Science, 2014, 90: 81-87.

DOI：10.1016/j.clay.2013.12.030

• Bentonite
• Sulfuric acid
• Surfactant
• Adsorption
• 2,4,5-trichlorophenol

Adsorption of the 2,4,5 trichlorophenol (TCP) from aqueous solution onto the surface of organo-bentonites was investigated spectrophotometrically. Natural bentonite was activated with sulfuric acid at 90 degrees C and exchanged with a set of 4 alkyltrimethylammonium bromides (alkyl = C12, C14, C16 and C18) to evaluate the effect of carbon chain length on the TCP adsorption. X-ray diffraction was used to study the change in the structural properties of the samples. The basal spacing of the activated-bentonite (AB) increased from 13.4 to 21.5 angstrom by intercalation of the cationic surfactants in the interlayer space of the clays. The intercalated cationic surfactants were characterized by Fourier transform infrared spectroscopy (FTIR). The surface areas of organo-bentonites were found to be much lower than that of AB. The contact time on the adsorption process was studied and the adsorption of TCP onto organo-bentonites followed pseudo-second-order kinetics. Adsorption isotherms were established and found to correlate with the Langmuir model with correlation coefficient of 0.998. Adsorption capacity of organo-bentonite increased with increasing the alkyl chain length. Results showed that TCP strongly interacted with AB exchanged with octadecyltrimethylammonium bromide (C18).

• 出版日期2014-3