Sorption of Methylene Blue on Polystyrene/Bentonite Film Composites

Abstract

The method of mechanochemical dispersion of bentonite in a polystyrene solution was used to modify the polymer and obtain film materials with improved sorption characteristics with respect to the methylene blue (MB) thiazine dye. It is found that the kinetics of the dye sorption are described by the pseudo-first-order equation. The sorption equilibrium is described by the Langmuir isotherm. The values of the limiting sorption capacity and specific surface area of the composite are determined. It is shown that the sorption efficiency of the dye on the PS/bentonite composite increases tenfold as compared with the non-modified sorbent; the extraction rate increases from 10 to 90%. The method of IR spectroscopy is used to show that MB sorption on polystyrene and the PS/bentonite composite is accompanied by electrostatic and donor–acceptor interactions of the reaction sites of MB with the hydroxyl–containing groups of the composite.