Preparation and characterization of ACF for the adsorption of BTX and SO₂

Abstract

Activated carbon fibers (ACFs) based on two precursors, namely viscose rayon and phenolic resin, were prepared by carbonization followed by physical activation with steam or CO₂. The prepared ACF samples were examined for their suitability of adsorbing common atmospheric gaseous pollutants, SO₂ and benzene, toluene, and m-xylene (BTX), under non-equilibrium conditions in a fixed bed tubular reactor. The textural and surface properties of the ACF samples were correlated with the adsorption characteristic of ACF for BTX and SO₂. The adsorption of BTX was found to increase with increase in either the BET area or micropore volume. In contrast, the surface groups containing electronegative oxygen atoms were found to have adverse impact on BTX adsorption. The adsorption of SO₂ was found to decrease with increase in the O-contents. The FTIR spectra and the elemental analysis revealed that the extent of oxygen groups (-OH, -COOH, -C=O, etc.) was larger in the steam-activated samples than in the CO₂-activated samples, regardless of the type of the precursor. The results obtained here are germane to a quantitative tailoring of activation routes for optimal performance of ACFs in pollution control.