Adsorption of SO 2 onto oxidized and heat-treated activated carbon fibers (ACFs)

M. A. Daley; C.L. Mangun; J.A. DeBarr; S. Riha; A.A. Lizzio; G.L. Donnals; J. Economy

doi:10.1016/s0008-6223(97)89612-1

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Adsorption of SO 2 onto oxidized and heat-treated activated carbon fibers (ACFs)

M. A. Daley·C.L. Mangun·J.A. DeBarr·S. Riha·A.A. Lizzio·G.L. Donnals·J. Economy

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Abstract

A series of activated carbon fibers (ACFs) and heat-treated oxidized ACFs prepared from phenolic fiber precursors have been studied to elucidate the role of pore size, pore surface chemistry and pore volume for the adsorption of SO 2 and its catalytic conversion to H 2 SO 4 . For untreated ACFs, the initial rate of SO 2 adsorption from flue gas was shown to be inversely related to pore size. At longer times, the amount of SO 2 adsorbed from flue gas was dependent on both the pore size and pore volume. Oxidation of the ACFs, using an aqueous oxidant, decreased their adsorption capacity for SO 2 from flue gas due to a decrease in pore volume and repulsion of the SO 2 from acidic surface groups. If these samples were heat-treated to desorb the oxygen containing function groups, the amount of SO 2 adsorption increased. This increase in adsorption capacity was directly correlated to the amount of CO 2 evolved during heat-treatment of the oxidized ACFs. The amount of SO 2 adsorbed for these samples was related to the pore size, pore surface chemistry and pore volume. This analysis is explained in more detail in this paper.

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M. A. Daley, C.L. Mangun, J.A. DeBarr, S. Riha, A.A. Lizzio, G.L. Donnals, J. Economy. 1997. Adsorption of SO 2 onto oxidized and heat-treated activated carbon fibers (ACFs). https://doi.org/10.1016/s0008-6223(97)89612-1

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