Preconcentration of trace nickel lons from aqueous solutions by using a new and low cost chelating polystyrene adsorbent

Abstract

A simple and reliable method has been developed using chelating polymeric adsorbent (PSAHSB) to preconcentration of trace amount of Ni(II) ions from aqueous solutions under static loading conditions, and their determination by Ultraviolet and visible (UV–Vis) absorption spectroscopy. The influences of some analytical adsorption parameters, such as pH, temperature and contact time, the ionization constants of chelating groups in the adsorbent and desorption process were investigated. Maximum adsorption ≥98% was achieved at pH 3–7 after 20 min of contact time and the relative standard-deviation values were ≤5%. Adsorbed metal ions have been desorbed with 10 mL of 2 M HCl acid with the detection limit of 0.0157 μg m−1. The Langmuir and Freundlich isotherm equations were used to describe adsorption behavior of the system at different temperatures. Kinetic and thermodynamic behavior of the adsorbent for Ni(II) ion preconcentration was also studied. The possible adsorption mechanism of Ni (II) ions onto modified adsorbent is also discussed. This method was applied efficiently to remove Ni (II) ions from environmental water samples.

Keywords

• Polystyrene
• Chelating groups
• Preconcentration
• Ionization constants
• Adsorption and desorption
• Kinetics