Investigation of the adsorption mechanisms of Pb(II) and 1-naphthol by β-cyclodextrin modified graphene oxide nanosheets from aqueous solution.

β-cyclodextrin decorated graphene oxides (β-CD-GO) was prepared by using an in-situ aggregation treatment, and used to remove inorganic (Pb(II)) and organic pollutants (1-naphthol) from water environment. The batch adsorption experiments of as-prepared β-CD-GO were carried out as a function of pH values, initial Pb(II) and 1-naphthol concentration, ionic strength, contact time and temperature. β-CD-GO kinetic results indicated that the adsorption was dominated by chemisorptions and followed a pseudo-second order model. The maximum adsorption capacities of β-CD-GO toward Pb(II) and 1-naphtholon the base of the Langmuir model were 149.56 and 207.6 mg·g-1 at 293 K, respectively. The thermodynamic experiments revealed that the adsorption of Pb(II) and 1-naphthol was spontaneous and endothermic. The surface compexation, hydrogen bonds and π-π interactions contributed to Pb(II) and 1-naphthol adsorption by means of the hydroxy and carboxyl functional groups on the surface of the β-CD-GO. The experimental results indicate that the β-CD-GO is an excellent composite for the elimination of Pb(II) and 1-naphthol from wastewater.