Microwave-assisted preparation and characterization of organo-attapulgites and comparison for 1-naphthol removal: equilibrium, kinetic, and thermodynamic studies

Abstract

AbstractIn this study, Na-attapulgite (Na-APT) was modified with octadecyl trimethyl ammonium chloride (OTMAC), sodium dodecyl sulfate (SDS), and the mixture of OTMAC and SDS using microwave-assisted technique. The prepared organo-attapulgites were characterized in detail. The combined analysis of characterizations indicated that surfactants were successfully introduced on the surfaces of attapulgite. A batch technique was adopted to investigate the removal efficiency of organo-attapulgites toward 1-naphthol under environmental conditions. The results showed that pseudo-second-order model and intraparticle diffusion model simulated the adsorption kinetic data better than that of pseudo-first-order model. The adsorption of 1-naphthol by organo-attapulgites fit reasonably well to Langmuir, Freundlich, and linear isothermal models. The negative values of ΔG° and ΔH° obtained from thermodynamic study indicated the spontaneous and exothermic nature of 1-naphthol adsorption on Na-APT and organo-attapulgites. Ba...