In the present work, mathematical modeling of SO2 removal reaction with CuO was performed by random pore model, modified grain model, and volume reaction model. In addition, experimental investigation of SO2 removal reaction by pure CuO was accomplished by thermogravimetry. The partial differential equations were obtained for a single pellet system and were solved by finite element method. Modeling predictions consist of conversion.time profiles of CuO at various temperatures (400 to 600 8C) and different inlet SO2 partial pressures (500 to 7000 ppm), which were compared with experimental results. The inherent rate constants and product layer diffusivities were evaluated between 400 and 600 8C. The sophisticated random pore model results were the most accurate predictions, while the simple volume reaction model failed to follow experimental conversions at the long times.