Enhanced PFBS adsorption via silver-impregnated activated carbon: Mechanistic insights and Thermodynamic analysis

This study investigates the effect of silver nanoparticle impregnation on the performance of activated carbon (AC) for perfluorobutane sulfonic acid (PFBS) adsorption. Using the deposition-precipitation method, three silver-impregnated activated carbon (SIAC) adsorbents were synthesized with varying silver contents: SIAC0.01 (0.15 wt%), SIAC0.1 (1.7 wt%), and SIAC1 (8.5 wt%). Among these, SIAC0.1 exhibited the highest adsorption capacity at 25 °C and was selected for detailed analysis. The adsorption mechanism of PFBS on SIAC0.1 was examined at 25, 35, and 45 °C, yielding key kinetic parameters, including reaction rate constants and activation energies. Additionally, the thermodynamic properties of the adsorption process, including ΔH^≠, ΔS^≠, and ΔG^≠, were evaluated. The findings reveal that silver nanoparticle impregnation significantly enhances the kinetic and thermodynamic favorability of PFBS adsorption, leading to a substantial increase in adsorption capacity. This work highlights the potential of silver-impregnated activated carbon as an effective adsorbent for PFBS removal.