Reactivity of Fe2O3 and Fe2O3-Al2O3 Mixture for Reduction of SO2 with CO

Article abstract of DOI:10.1246/bcsj.55.1447

Catalytic reactivities of α-Fe2O3 powder (-200 mesh) and a α-Fe2O3-γ-Al2O3 powder mixture prepared by mechanical mixing, which were preheated at 360-700 deg C, were studied for the reduction of SO2 with CO by means of both a reaction gas-chromatographic technique using CO, SO2, and 2CO-SO2 pulses and the powder X-ray analysis.The reactivity of Fe2O3 decreases with increasing preheating temperature, which is explained on the basis of redox reactions between Fe2O3 and nascent (Fe3O4): 6Fe2O3+2CO->4(Fe3O4)+2CO2 and 4(Fe3O4)+SO2->6Fe2O3+1/2S2.It is considered that the reactivity of Fe2O3 is attributable to the activity of (Fe3O4).The lifetime of active (Fe3O4) is within about 1 min, and the activity and lifetime of (Fe3O4) is increased by interfacial reaction between Fe2O3 and Al2O3 at 700 deg C.The activity maximum in the Fe2O3-Al2O3 system preheated at 700 deg C is attained at 70-75 wtpercent Fe2O3.