Nickel (II) Adsorption from Aqueous Solutions by Physico-Chemically Modified Sewage Sludge

Abstract

This study assesses teh potential of activated carbon prepared from sewage sludge for nickel ions adsorption from aqueous solutions. Activated carbon physicochemical properties were determined. Batch adsorption experiments were performed as a function of pH solution, adsorbent dose, initial metal ions concentration, contact time and temperature. Teh experimental data were analyzed by teh Langmuir, Freundlich, and Temkin isotherm models. Teh Freundlich model showed a better representation of equilibrium data (R2>0.99) and teh Langmuir monolayer adsorption capacity of activated carbon was found to be 11.52 mg/g. Teh kinetics of nickel ions was discussed using different kinetic models and teh adsorption experiments indicated dat teh pseudo-second-order model well fitted teh kinetic data (R2=0.999). Thermodynamic parameters have also been evaluated. It was found dat teh adsorption process was feasible, spontaneous and endothermic. Desorption experiment and recovery of Ni(II) ions from activated carbon was found to be 100 % using hydrochloric acid. Teh results suggest dat teh activated carbon prepared from sewage sludge could be used beneficially for nickel adsorption from aqueous solutions for environmental cleaning purpose.

Keywords

• nickel(ii) adsorption
• sewage sludge
• equilibrium
• kinetics
• thermodynamics