Adsorption characteristics of Ni(II) from aqueous solution and industrial wastewater onto Polyaniline/HMS nanocomposite powder

The purpose of this research work is to investigate sorption characteristic of Polyaniline/Hexagonal Mesoporous Silica (PANI/HMS) nanocomposite powder for the removal of Ni(II) ions from aqueous solutions. The adsorbent is characterized using FE-SEM, TEM, FTIR, XRD and BET surface area. The sorption of Ni(II) ions by batch method is carried out and the optimum conditions are investigated. Three models, i.e., Morris–Weber, Lagergren and Pseudo second order have been tested to track the kinetics of removal process. The Langmuir, Freundlich and D–R are subjected to sorption data to estimate sorption capacity, intensity and energy. The thermodynamic parameters (ΔH, ΔS and ΔG) are evaluated, as well. These parameters showed that the adsorption of Ni(II) onto PANI/HMS is feasible, spontaneous and endothermic under studied conditions. It is found that temperature has a positive effect on the removal efficiency. It can be concluded that PANI/HMS is potentially able to remove Ni(II) ions from aqueous solutions. Also it is achieved more than 86% desorption efficiency using 0.1 M H2SO4 and reusing of adsorbent shows high ability in the Ni(II) removal from aqueous media.