Acoustic energy isotherms: An emergent approach for textural characterization of activated carbons

Acoustic Emission Analysis (AEA) for textural characterization of granular activated carbons (GACs) is an interesting alternative for assessing the GAC volume of pores in a rapid, sensitive and reliable way. Correlations between AEA and conventional methods have demonstrated its potentialities for textural characterization of high-porosity materials. In this study, commercial GACs with different porous characteristics were compared and correlated by applying volumetric gas sorption (N-2 at 77 K, CO2 at 273 K), Hg porosimetry and AEA. The energy, amplitude and power of the acoustic signal produced during GAC immersion in water are used as parameters to correlate with textural characteristics of the carbons. The found relationship between conventional porosity assessment techniques and acoustic parameters demonstrated the potentialities of the acoustic method as complementary technique of exploring textural properties of high-porosity materials.