Use of core-shell polyaniline/polystyrene nanocomposite for removal of Cr (VI)

In this study the ability of polyaniline/polystyrene as high performance synthetic adsorbent for the adsorptive removal of Cr (VI) ions from aqueous solutions was investigated. To carry out the investigation, the batch operation method was employed. As well, the effects of various experimental parameters like pH, adsorbent dosage, contact time and the temperature on the removal efficiency were studied. The optimum conditions for Cr (VI) removal are achieved with pH 4, adsorbent dosage of 15 g L-1, and 30 min equilibrium time. It is worth noting that the adsorption of Cr (VI) followed pseudo-second-order kinetics. The equilibrium adsorption isotherm was better described by Temkin adsorption isotherm model. The adsorption capacity (q(max)) of PAn/Ps for Cr (VI) ions in terms of monolayer adsorption was 19 mg g(-1). The change of entropy (Delta S-0) and enthalpy (Delta H-0) were estimated to be -0.08455 J (mol K)(-1) and -29.04 kJ mol(-1), respectively. The negative value of Gibbs free energy (Delta G(0)) indicates feasible and spontaneous adsorption of Cr (VI) on PAn/Ps.