Johnson Matthey DOC verification extended after in-use tests

24 September 2010

The US Environmental Protection Agency (EPA) has extended the verification of the Johnson Matthey retrofit diesel oxidation catalyst (DOC) to cover model years 1988-2006 for both EGR and non-EGR heavy-duty diesel engines—the broadest coverage in the industry. In addition, the EPA has raised the DOC PM reduction verification level to 25% on engine model years from 1998 to 2003.

The extension was triggered by the results of the mandatory in-use tests performed by Johnson Matthey on its DCC® (Diesel Catalytic Converter). The results of the Phase I and Phase II tests also showed that the company’s DOC actually reduced PM emissions by an average of 27% and, in some of the tests, could achieve as much as a 32% reduction. The catalyst maintained its performance after 100,000 miles or more.

Eight DOC’s were tested, four for Phase 1 (25% of warranty period) and four for Phase II (75% of warranty period). All testing, baseline and device, was done using ultra-low sulfur diesel fuel to represent today’s real-world operation.

Johnson Matthey’s DCC converter also reduces HC and CO emissions by more than 40%. The catalyst, designed to operate with 500 ppm low sulfur diesel fuel, was formulated to minimize sulfate formation.

Source: Johnson Matthey