Adsorption of Fluoride From Aqueous Solution by Eucalyptus Bark Activated Carbon: Thermodynamic Analysis



Mahvi AH^{1, 2} ; Kord Mostafapour F³ ; Balarak D³
Source: Fluoride Published:2019

Abstract

In this experimental study, batch adsorption experiments were implemented to survey the potential of eucalyptus bark activated carbon (EBAC) in the adsorption of fluoride (F-). The studied adsorbent was synthesized using the chemical activation method in the presence of phosphoric acid. The effect of several parameters, e.g., the contact time, the initial F- concentration, and the temperature on the F-adsorption onto the EBAC was investigated under constant values for the pH (6.5) and the adsorbent dosage (2 g/L). The calculation of the standard free energy changes (∆G0), the standard enthalpy change (∆H0), and the standard entropy change (∆S0) were carried out at different temperatures and initial F- concentrations. The ∆G0 values were negative and the ∆H0 values and the ∆S0 values were positive at all temperatures and concentrations which suggests that the F- adsorption onto the EBAC was a spontaneous and endothermic process. © 2019, ISFR.