Study on the Optimized Design of DeSOx Filter Operating at Low Temperature in Diesel Exhaust

The removal of sulfur dioxide (SO2) contained in the combustion exhaust gas from medium-scale facilities is necessary because of its role as an air pollutant. In this study, we focus on dry DeSO(x) filters that use simple desulfurization materials to capture SO2; in particular, we used manganese dioxide (MnO2) that takes part in the sulfation (MnO2+SO2 -> MnSO4). We determined the reactivity of high-surface-area MnO2 (HSSA MnO2) with SO2 using thermogravimetry. We obtained the desulfurization rate for a sample of MnO2 that was wash-coated on a monolith. The MnO2 sample, having a specific surface area of 250 m(2)/g, absorbed 0.43-0.45 g(SO2)/g(MnO2). Under this experimental condition, the conversion of the sulfation was dependent on the amount of the supported MnO2. The absorption efficiency of these samples was more than 90.0%. Based on our results, we estimated that 20 m(3) of absorbent was required to capture the exhaust gas of an ocean ship with a crossing time of 20 d, operating at 8,500 kW power at 450 degrees C.