Microporosity of activated carbons produced from heat-treated and fractionated pitches

Activated carbons with degrees of burn-off ranging from 12 wt.% to 60 wt.% have been prepared from toluene-insoluble (T.I.) fractions of a heat-treated A240 petroleum pitch. After toluene fractionation, the resulting pitches have been stabilized, carbonized and then activated using carbon dioxide at 1173 K. Characterization by high pressure carbon dioxide adsorption has been performed in order to determine the properties of activated carbons and to evaluate their performances for adsorption refrigerating machines. Microporous properties are influenced by pitch composition resulting from toluene fractionation and residual γ-resins inhibit the microporosity development. Due to their high microporous volume, activated carbons prepared from extensively γ-resins extracted pitches appear appropriate for cooling applications.