Uniform polyaniline microspheres: A novel adsorbent for dye removal from aqueous solution

Uniform polyaniline (PANI) microspheres were synthesized by a facile polymerization of aniline monomer in the acidic medium. The structure and morphology of PANI microspheres were characterized by means of FTIR spectrometer, X-ray diffractometer (XRD), scanning electron microscope (SEM) and transmission electron microscope (TEM). Adsorption characteristics of PANI microspheres were examined using methyl orange (MO) as adsorbate. Batch adsorption experiments were carried out to investigate adsorption kinetics and isotherms of PANI microspheres. Adsorption equilibrium studies showed that MO adsorption followed Freundlich model. The adsorption kinetics was best described by pseudo-second-order model. The results indicated that PANI microspheres can be used as a novel. effective and low-cost adsorbent material for dye removal. (C) 2010 Elsevier B.V. All rights reserved.