Adsorption of chloroanilines from aqueous solutions on the modified halloysite

The results show that the adsorption of 4-chloroaniline was greatly enhanced by using a sulfuric acid-treated halloysite, as compared to the unmodified halloysite. A comparison of kinetic models applied to the adsorption of chloroanilines on an acid-treated halloysite was evaluated for pseudo first-order, pseudo second-order, and intraparticle diffusion kinetic models. The chemisorption pseudo-second order kinetic model was found to correlate the experimental data well. The adsorption mechanism of acid-treated halloysite -chloroaniline system complied well with the Langmuir model in the case of 4-chloroaniline and 3,4-dichloroaniline and with the Freundlich model for 3-chloroaniline.