Sulfur Storage and Discharge Behavior on Flow-Through Type Oxidation Catalysts

Sulfur storage/discharge behavior on a flow-through type oxidation catalyst (FTC) was investigated by engine dynamometer tests and laboratory tests, and the following results were obtained.

In FTC wherein active Al₂O₃ was used as a substrate for supporting catalytic components, sulfur was stored in the form of aluminum sulfate in high temperature region while sulfate were adsorbed or adhered to the catalyst surface layer to be stored thereon in low temperature region.

Although aluminum sulfate formed in high temperature region was relatively stable, sulfate stored in low temperature region were desorbed easily when the temperature rose.

Therefore, it was attempted to optimize the substrate deposited catalytic components. And, FTC which would inhibit adsorption of sulfate was achieved successfully.