Pollution Control Technologies for Use with High Sulfur Fuels

The state-of-the-art pollution control technology for highway diesel engines is the NOx storage–release (NSR) trap and the catalytic diesel particulate filter (CDPF). The NSR incorporates precious metal and basic functions for oxidizing NO and adsorbing NO2. This makes the device vulnerable to the presence of sulfur oxides in exhaust gas; the adsorber is irreversibly poisoned at fuel sulfur levels of >15 ppm, requiring use of ultra-low sulfur diesel (ULSD). Because of the sulfur levels of JP 8, pollution control devices employed in civilian automobiles are not applicable to the military. This proposed project will apply Eltron’s sulfur tolerant catalytic technology for after-treatment of exhausts from logistic fueled engines. The technology is based on a passive lean NOx catalyst which has demonstrated activity greatly exceeding that of competing passive lean NOx catalysts for NOx removal from diesel exhaust at an estimated current cost of ~$350 (versus ~$1400 for a catalytic NOx trap) for a heavy vehicle. Phase I will validate previous results, optimize catalysts, and test the catalyst in the exhaust of an engine operating on logistic fuel. Phase II will demonstrate a retrofit catalyst which outperforms existing technologies, while minimizing costs while transitioning the technology to the Army procurement system.