Physical and adsorptive characterizations of immobilized polyaniline for the removal of methyl orange dye

Abstract

Synthesized polyaniline (PANI) powder mixed with ENR-PVC polymer blend adhesive was immobilized on glass plates for the adsorption of methyl orange (MO) dye. The immobilized PANI composite was made up of plasticized PANI aggregates and was in a doped state. The incorporation of ENR-PVC blend in PANI slightly reduced the surface area from 9.2 to 8.5 m2 g-1, and its presence was confirmed through FTIR. The adsorption process was highly dependent on the aeration rate, and the pH of MO solution in which 40 mL min-1 and ambient pH (6.5) was selected as the working conditions. The process of MO uptake onto the immobilized PANI obeyed the pseudo-second-order kinetic model, while intra-particle diffusion was found to dominate the adsorption process. The qm of the immobilized PANI was 77.3 mg g-1 for MO uptake and obeyed the Freundlich isotherm model. The thermodynamic study revealed that the adsorption process of immobilized PANI was spontaneous and unfavorable at high temperature. The immobilized PANI was found to be comparable with other PANI based adsorbents in term of cost, recyclability and adsorption efficiency.