Determination
of Thermodynamic Parameters of Phenol Adsorption onto Sewage Sludge based Adsorbent
by different Methods
Bousba Salim, Bougdah Nabil and Messikh Nabil
Res. J. Chem. Environ; Vol. 27(11); 1-6;
doi: https://doi.org/10.25303/2711rjce01006; (2023)
Abstract
The aim of this study is the determination of thermodynamic parameters of the adsorption
of phenol onto sewage sludge based adsorbent (SSBA) by different methods. Thermodynamic
parameters are calculated from three equilibrium constants (Kc) that were derived
from the isotherm constants of Langmuir (KL), the distribution coefficient (Kd)
and Freundlich isotherm exponent (n). For this, removal of phenol from aqueous solutions
by adsorption under batch equilibrium experimental conditions at 293, 303 and 328
K was investigated. All values obtained for ΔG° are negatives this indicated that
the adsorption process of phenol on the SSBA is spontaneous and thermodynamically
feasible process.
We also note that as the temperature increases, the absolute value of ΔG° decreases,
it shows that the adsorption is more spontaneous at low temperatures. All values
of the standard enthalpy ΔH° are negative and less than 35 kJ.mol-1 which confirm
that the process is an exothermic physisorption. The negative values of the standard
entropy ΔS° clearly show that the arrangement of phenol molecules is more preferred
on the surface of the adsorbent.
