Diesel Particulate SOF Emissions Reduction Using an Exhaust Catalyst

The reduction of Diesel particulate SOF, including the PAH was investigated using a conventional one pass Englehard PTX exhaust catalyst, which formed part of an underground mine Diesel exhaust clean up system. The reduction in total particulate mass and the SOF mass was approximately 70% for exhaust temperatures above 250 C, which was better than for the low MW gas phase UHC. For the PAH and other high MW compounds in the SOF a 70% reduction in the mass emissions was achieved for temperatures above 170 C. This greater catalytic efficiency at lower temperatures for high molecular weight compounds was attributed to these compounds, at the catalyst temperature, being in the liquid phase absorbed into the particulate and in direct, locally concentrated, large surface area contact with the catalyst surface. The low MW compounds of the SOF would be in the gas phase at the catalyst temperature.