The primary objective of this project was to carry out a thorough investigation of the kinetics of the interaction of SO{sub 2} gas with CaO particles at temperatures between 25{degree}C and 1000{degree}C. Our goal was to develop the new technique of FTIR (Fourier Transform Infra Red) spectroscopy for studies of the SO{sub 2}--CaO interaction so as to determine not only the kinetics but also the nature of the chemical products of the reaction for temperatures to 1000{degree}C. Further, our goal was to determine the effect of oxygen on the kinetics and products of the reaction. In addition, techniques of ESR (Electron Spin Resonance) spectroscopy and TGA (Thermogravimetric Analysis) were to be employed to support these studies. It was hoped that results of these studies would clear many of the inconsistencies reported in literature on the sulfation of CaO. Results of these studies as well as results on the interaction of SO{sub 2} with calcined CaCO{sub 3} and MgCO{sub 3} (calcined at 700{degree}C), for temperatures up to 700{degree}C, are given in this report. 44 refs., 23 figs., 9 tabs.