Kinetics of reaction of CaCO3 with SO2 and O2 below 650°C

Abstract

The reaction of CaCO₃ with SO₂ alone or with O₂ has ben investigated, taking into account previously obtained results on the reaction of CaSO₃ with SO₂ or O₂. The main kinetic characteristics of the fixation of SO₂ on CaCO₃ in the presence of oxygen have been determined. It is shown that the blocking of the reaction at low degrees of transformation can be explained by the extremely rapid reaction of CaSO₃(formed by the reaction of CaCO₃ with SO₂) with O₂; the imperviousness of the CaSO₄ layer so formed and the throttling of the pores because of the higher molar volume of CaSO₄ eventually prevent the reaction from proceeding further.