THE FORMATION AND CONTROL OF SULFURIC ACID EMISSIONS OVER AUTOMOTIVE CATALYSTS 770198
In order to find a way to minimize sulfuric acid formation while maintaining high HC and CO conversion, the effect of temperature, air-fuel ratio, space velocity and catalyst metal composition on SO2 conversion was studied. Both pelleted and monolithic catalysts were investigated using an engine dynamometer and a small diameter dilution tunnel. The effect of engine operating conditions on SO2 conversion was clarified and an advantageous shape for the catalytic converter was found. Thirteen pelleted and four monolithic catalysts were tested with rhodium showing a remarkable effect on HC conversion selectivity.