Modeling of the relationship between the thermodynamic parameters ΔH° and ΔS° with temperature in the removal of Pb ions in aqueous medium: Case study

Abstract

In this work, the removal of Pb from six different adsorbents was evaluated, considering that ΔH° and ΔS° depend on temperature, and the implications of the strong correlation between ΔH° and ΔS° on the adsorption of Pb in the studied systems. The obtained results showed that there is a strong causal correlation between ΔH°-ΔS° common to the studied systems. The enthalpy–entropy relationship allowed to determine the isokinetic temperature. This suggests that the nature of the active sites (adsorbents) and the chemical species of the Pb could be similar, and that the adsorption mechanism could be driven by weak interaction forces.