Preparation and characterization of anion-cation organopalygorskite for 2-naphthol removal from aqueous solution

In this study, anion-cation organopalygorskite (ACOP) was prepared using microwave-assisted technique and characterized in detail. The elemental analysis and Fourier transform infrared (FTIR) spectroscopy analysis indicate that sodium dodecyl sulfate (SDS) and dioctadecyl dimethyl ammonium chloride (DDAC) have been successfully coated on the surface of palygorskite. The prepared ACOP was used for the preconcentration of 2-naphthol from aqueous media. The effects of pH, ionic strength, agitation time and temperature were investigated. The sorption kinetic data can be well fitted by the pseudo-second-order model. The Langmuir, Freundlich and Linear models were applied to simulate the sorption isotherms and the results showed that the Freundlich model fitted the experimental data best. The thermodynamic parameters calculated from the temperature-dependent sorption isotherms indicated that the sorption of 2-naphthol on ACOP was an exothermic and spontaneous process. By integrating the above-mentioned laboratorial results together, the preconcentration of 2-naphthol on ACOP is considered to be a combination of surface sorption and partitioning mechanism. The findings herein suggested that ACOP can be potentially used as a cost-effective material for the preconcentration of actual organic contaminant-bearing effluents.