Adsorption of Humic Acid from Aqueous Solution onto PAA Nanofiber: Thermodynamic Study

The potential of polyacrylic acid (PAA) nanofiber prepared by the electrospinning technique for the humic acid (HA) adsorption from aqueous solution was investigated. In this study, the adsorption experiments were carried out to investigate the effect of temperatures in a batch system. From experiment it can be seen that the HA adsorption using PAA nanofiber increased with increasing temperature. Thermodynamic parameters data indicated that the HA adsorption process was non-spontaneous and endothermic under the experimental conditions, with the Gibbs free energy (∆G o ) in the range of 1.721-0.980 kJ mol -1 , enthalpy (∆H o ) and entropy (∆S o ) of 7.24 kJ mol -1 and 18.52 J mol -1 K -1 , respectively.