Catalytic Role of Process Dust in SO 2 -to-SO 3 Conversion in Flash Smelting Heat Recovery Boilers

The aim of this work is to examine the catalytic role of copper smelter, copper converter, and nickel smelter process dusts in SO 2 -to-SO 3 conversion at 750°C. To clarify the role of specific oxides in greater detail, synthetic dusts containing varying concentrations of either CuO or Fe 3 O 4 were also studied. All studied dusts catalyzed SO 3 conversion. Among the industrial flue dusts, the highest concentration of SO 3 formed in the presence of copper smelter dust. Comparing individual oxides, CuO had a greater impact on the SO 3 formation. Such catalytic effects of smelter dusts may lead to SO 3 concentrations in the process gas so high that sulfuric acid dew point corrosion may occur.