A kinetic study of the reaction between sulfur trioxide or sulfur dioxide and oxygen mixtures and a number of basic oxides was carried out using a thermogravimetric analyser under the following ...conditions: (1) temperature = 450-1100 K; (2) concentration of SO(,2) or SO(,3) = 0.06-0.63 moles/m('3); (3) concentration of O(,2) = 0-2.9 moles/m('3); (4) particle radius = 0.071-0.303 mm; (5) type of oxides = ZnO, MgO, CaO (studied extensively), CdO, La(,2)O(,3), HgO, CuO, BaO, Sc(,2)O(,3) and oil shale (several tests). The laboratory data were interpreted using the following models: the changing grain size model, the changing pore size model with cylindircal or rectangular pores, partially sintered spheres model, random pore model, volume reaction model and the distributed pore model. The distributed pore model was found to give the best representation of the data up to the theoretical maximum conversion of the basic oxide based on the volumetric limitation of reducing the porosity of the particle to zero. When the reaction proceeded beyond this limitation the partially sintered spheres model was found to give the best representation of the data. In this region the model was revised to allow diffusion into the particle after pore closure at the surface was predicted by the model. An existing pilot plant reactor was modified and used for testing a sulfur removal scheme at the Grand Lake Generating Station of the New Brunswick Electric Power Commission in Minto. The scheme is based on the simultaneous catalytic oxidation of SO(,2) to SO(,3) and its subsequent reaction with a basic oxide. The tests indicated that the catalytic oxidation could be carried out successfully in the dust laden gas, but the rate of reaction between the SO(,3) and the basic oxides was too slow for a reasonable gas residence time.
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