关键词: 凹凸棒石, SO₂, 热处理, 烟气脱硫

Abstract: Palygorskite as an excellent adsorbent material shows a predominant performance on the adsorption of small gaseous polar molecules, which can be remarkably improved by suitable thermal treatment. In this study, the SO₂ removal from the flue gas is investigated with the palygorskite treated at different temperatures. The structural transformation of palygorskite desulfurizer during the heat treatment process was characterized by XRD，BET and TPD. A correlation between structural characteristics and desulfurization performance of palygorskite adsorbent was discussed. Results indicate that, as the heat treatment temperature increases, the micro-crystal structure of palygorskite displays significant step changes, which is suggested to be closely related to the removal of water in different forms from palygorskite surface. The adsorption capacity of SO₂ on palygorskite first increases and then decreases as the heat treatment temperature increases. Based on these results, it can be deduced that the water adsorbed on the surface and that in the pores of palygorskite inhibit the adsorption of SO₂, but the crystalline water is favorable for SO₂ adsorption.

Key words: palygorskite, SO₂, heat treatment, flue gas desulfurization