Manganese removal from aqueous media using polyaniline nanocomposite coated on wood sawdust

• The PAn and PAn/HPC can be uniformly coated on the surface of sawdust.
• Products were investigated in terms of morphology and chemical structure.
• Surfactant can increase the manganese removal efficiency.
• Optimum conditions for Mn2+ removal are 10 g/L of adsorbent dosage in pH 10.

In the present study the adsorption of manganese ions from aqueous solution by polyaniline/sawdust (PAn/SD) nanocomposite is experimentally investigated. The experiments were conducted to evaluate the effect of various experimental parameters i.e., pH, adsorbent dosage and contact time on the removal efficiency. The results showed that optimum conditions for manganese removal were found to be at pH of 10, adsorbent dosage of 10 g/L and equilibrium contact time of 30 min. The kinetic of adsorption system have been studied based on the assumption of a pseudo-second order rate law. The experimental results have been analyzed using a pseudo-Langmuir adsorption isotherm and a pseudo-Freundlich adsorption isotherm models. The Freundlich adsorption isotherm model was found to represent the equilibrium adsorption isotherm better than Langmuir adsorption isotherm. According to the evaluation using the pseudo-Freundlich model, the monolayer adsorption capacity (qmax) of PAn/SD for manganese ions was obtained to be 58.824 mg/g.